OBJECTIVE:To assess the technical feasibility and functional, metabolic, and structural myocardial integrity of the donor heart after four hours of direct coronary oxygen persufflation (COP). METHODS:This research was carried out on three-month-old minipig siblings weighing 23-36 kg. Cardiac arrest was achieved by administrating two liters of Bretschneider's cardioplegic solution (histidine-tryptophan-ketoglutarate [HTK]) (Custodiol®, Germany) into the aortic root. Orthotopic heart transplantation was performed after three hours of cardiac arrest. RESULTS:A statistically significant decrease in cardiac output was observed in both groups (from 3.36 ± 0.36 l/min and 3.72 ± 0.52 l/min in the HTK group and modified HTK + COP to 2.35 ± 0.52 l/min and 2.15 ± 0.34 l/min, respectively) (Р<0.05). Differences between both groups were insignificant (P>0.05). Cardiac output was 2.99 ± 0.45 l/min and 2.48 ± 0.58 l/min (Р>0.05) in both groups after 120 min of cardiac recovery. Lactate dehydrogenase, creatine phosphokinase-MB, and troponin I changes in coronary sinus blood were significantly higher in the early reperfusion period. Statistical insignificance was observed between both groups (P>0.05). Myocardial oxygen consumption was 8.2 [7.35; 9.35] ml-О2/min/100 g and 7.7 [6.75; 10.12] ml-О2/min/100g in both groups (P>0.05). Histological examinations demonstrate no significant myocardial ischemic injury in the persufflation group. CONCLUSION:The study demonstrated technical feasibility and safety of direct coronary persufflation for four hours during ex vivo donor heart conditioning. However, no significant advantages of direct COP were observed over the standard cold preservation protocol.

OBJECTIVE:To evaluate the effects of intracoronary iopromide (Ultravist®, Germany) administration on the recovery of cardiac pump function and cardiomyocytes metabolism during ex vivo cold preservation of pig hearts in the early posttransplant period. METHODS:Three-month-old mini pigs weighing 73 ± 2.8 kg were used as experimental models (n=12). Physiological parameters were obtained with the IntelliVue MP70 system (Philips, Netherlands). Blood samples were taken from the coronary sinus to evaluate myocardial ischemia markers - troponin I, creatine phosphokinase-MB, lactate dehydrogenase, and lactate - and apex biopsy was performed before and after the ischemia period according to the protocol. Myocardial samples were taken from the left ventricle and prepared according to the protocol either. RESULTS:Twelve orthotopic heart transplantations were performed during the study. Sample size was divided into two groups with six each. Cardiac output was 5.11 (4.99; 5.41) l/min and 5.77 (4.97; 6.62) l/min (P-0.0009) after 120 minutes of cardiac activity in both groups. Change of lactate dehydrogenase, creatine phosphokinase-MB, and troponin I levels in the coronary sinus blood were significantly higher in the early reperfusion period. However, there were no statistically significant differences between the groups (P>0.05). Myocardial oxygen consumption was considerably reduced during reperfusion but returned to baseline by 60 minutes of postischemia without significant differences between groups (P>0.05). CONCLUSION:We observed that intracoronary iopromide administration was safe during the ex vivo stage cold preservation phase of the study. Intracoronary iopromide administration did not affect cardiac pump function and cardiomyocytes metabolism in the early posttransplant period.

Background. Heart transplantation is currently the treatment of choice for patients in terminal stages of chronic heart failure. The critical shortage of donor organs and the growing need for heart transplantation necessitate the expansion of donor selection criteria, including the estimated ischemia time of the donor heart. Despite numerous studies, the issue remains regarding the safe cold ischemia time; no definite limit to the acceptable preservation time is known and no relevant pathomorphological data are available on the state of the donor heart myocardium at different time parameters. Objective. To comparatively assess the features of cardiomyocyte pathomorphology and expression of protein markers (actin and desmin) in the myocardium of a donor heart prior to the main stage of orthotopic heart transplantation. Methods. The work adopted the design of an observational clinical study, which was prospective in nature. The study used intraoperative myocardial biopsy specimens of the left atrial appendage from donors aged up to 60 years, following cold ischemia of the transplant in Bretschneider solution (Dr. Franz Köhler Chemie GmbH, Germany) lasting up to 240 minutes (Group 1, n = 10) and over 240 minutes (Group 2, n = 7). The nature of pathomorphological myocardial transformation in the left atrial appendage of the donor heart was determined at different cold ischemia times. Histological myocardial sections were stained with hematoxylin and eosin according to standard procedures. After that, they were further studied using light and polarization microscopy; the immunohistochemical method was used to analyze the expression of actin and desmin. Morphometry was performed using the ImageJ 1.48v software (USA). In the analysis of actin and desmin amount, the area of DAB(3,3′-diaminobenzidine)-positive products of the immunohistochemical reaction was estimated as a percentage of the image area. The volume density of immunohistochemically detectable actin and desmin was determined using 20 images at a magnification of 40×10. In order to study the intensity of the immune reaction, a semiquantitative method was used, which involved counting the number of cells in 25 randomly selected fields of view. The types of myocardial contracture damage were assessed via polarization microscopy. Results. Patients included in the first and second groups were comparable in terms of mean age and anthropometric indices. The mean age of patients amounted to 50 [44;59] years in Group 1 and 50 [49;50] years in Group 2, р = 0.193. The body mass index was 25 [22;27] in Group1 and 25 [21;31] in Group 2, р = 0.288. Both groups showed male predominance: 8 (80%) in Group 1 and 6 (85.7%) in Group 2, р = 0.256. The comprehensive morphological assessment of ischemic myocardial damage at different cold ischemia times revealed the uniformity and reversibility of changes in cellular structures (in both groups) that take the form of I–II class contractures, lysis changes in individual cardiomyocytes (only in Group 2), preserved immunohistochemical reactions to actin and desmin in both groups at their average intensity and the complete absence of areas showing no reaction to desmin, which gives an idea about the degree of preservation of their macromolecular structure. Conclusion. The obtained study results showed that due to having a balanced elemental composition that determines the metabolic protection of cells and their ionic balance, the Bretschneider solution effectively protects the donor heart during its transportation, with the myocardial cold ischemia lasting up to 240 min and more.

Introduction. The effects of the synthetic glucocorticoid dexamethasone on target organs are mediated by the interaction with the glucocorticoid receptor, but the effects of the drug on the intact brain have been poorly studied. We aimed to look at a one-time and repeated exposure to a two-dose dexamethasone on the expression of the glucocorticoid receptor and cellular changes in the prefrontal cortex over time. Materials and methods. Male C57Bl/6 mice aged 7–8 weeks received a one-time or multiple intraperitoneal injections of dexamethasone in doses of 1.0 or 2.5 mg/kg. Structural changes in the prefrontal cortex were analyzed on paraffin sections stained by hematoxylin and eosin 90 days after the injection. The expression of the glucocorticoid receptor was studied with immunohistochemistry using monoclonal antibodies and quantitative analysis. Results. A histological study of the prefrontal cortex exposed to a two-dose dexamethasone revealed the absence of an obvious dose dependence and the reversibility of dystrophic and hydropic changes. The most pronounced changes were revealed with a one-time administration of the drug (on day 7) and repeated administration (on day 15) while normal tissue architecture returned to that of the control groups. The expression level of the glucocorticoid receptor after a one-time dexamethasone injection at a dose of 2.5 mg/kg showed a significant growth (р<0.05) on days 3 and 10 compared to that of the control group, while after multiple dexamethasone injections, the GR expression decreased on day 15, but by day 30 it returned to its initial level. Conclusion. Stereotypical dystrophic and hydropic changes in the prefrontal cortex during exposure to two different regimens and dexamethasone doses developed on days 7 and 15. We revealed an opposite effect of 2.5 mg/kg dexamethasone administration regimens on the expression of the glucocorticoid receptor in the prefrontal cortex of mice relative to the control group: at a one-time administration the expression increased by 8.1% on day 10 and at multiple administration the expression grew by 9.9% on day 15. Keywords: dexamethasone, glucocorticoids, brain, prefrontal cortex, glucocorticoid receptor, immunohistochemistry

Introduction. Heart transplantation is currently the mainstay of treatment for the end-stage chronic heart failure patients. To date, there is no consensus on the time criteria for cold ischemia of the donor heart. Despite a large number of studies, the question about the level of damage of cardiomyocyte cytoskeleton proteins at different terms of cold ischemia remains unresolved; there is no clear time limit of acceptable preservation time and corresponding pathomorphological data on the state of their structure at ischemic and reperfusion damage. Aim. An analysis of pathomorphological characteristics of cardiomyocytes and the expression of E-cadherin, protein from the family of cell adhesion molecules in the myocardium of the donor heart at different terms of cold ischemia. Materials and methods. Intraoperative biopsies of the myocardium of the left atrial appendage of donors aged up to 60 years after cold ischemia with Custodiol solution duration up to 240 min (group 1, n = 10) and over 240 min (group 2, n = 7) were used. Histological sections of the myocardium were stained according to the standard procedure with hematoxylin and eosin. Their further study was carried out by light microscopy, and to assess the E-cadherin expression immunohistochemistry was used. Results. The assessment of cardiomyocyte pathomorphology under conditions of different duration of myocardial cold ischemia revealed homogeneity and reversibility of changes in cellular structures, steady-state expression of the cell adhesion protein, E-cadherin at the sites of intercalated discs in patients of both groups. Conclusion. The results showed that the activity of E-cadherin under cold myocardial ischemia with Custodiol solution for 240 min and over 240 min remains in steady-state, indicating the preservation its macromolecular structure and functional polarity of myocardial muscle cells.

Introduction. Glucocorticoids are actively used in the treatment of various diseases, however their long-term use leads to numerous negative side-effects, the molecular mechanisms of which remain poorly understood. Aim. Study of the short-term (1–10 days) effects of various doses of dexamethasone (Dex) (0,1–10 mg/kg) on the expression of the glucocorticoid receptor (GR, Nr3c1), core proteins of main proteoglycans and heparan sulfate metabolism-involved genes, as well as the content of carbohydrate macromolecules of glycosaminoglycans in the brain tissue of experimental animals. Materials and methods. In the study, C57Bl/6 mice were used. The expression of GR, proteoglycan core proteins and heparan sulfate metabolism-involved genes was determined by real-time polymerase chain reaction with reverse transcription. The content and localization of GR protein molecule were studied by Western blot and immunohistochemical analysis, and the glycosaminoglycan content was determined by dot-blot analysis and Alcian Blue staining. Results. It was shown that a single Dex administration leads to fast (1–3 days) short-term activation of GR expression (+1.5 times, p <0.05), proteoglycan’s genes (syndecan-3, Sdc3; perlecan, Hspg2; phosphacan, Ptprz1; neurocan, Ncan; +2–3-fold; p <0.05) and heparan sulfate-metabolism-involved genes (Ndst1, Glce, Hs2st1, Hs6st1, Sulf1 / 2; +1.5–2-fold; p <0.05) in the mouse brain, with a return to control values by 7–10 days after Dex administration. At the same time, the effect of Dex on carbohydrate macromolecules of glycosaminoglycans was more delayed and stable, increasing the content of low-sulfated glycosaminoglycans in the brain tissue in a dose-dependent manner starting from day 1 after Dex administration. Highly-sulfated glycosaminoglycans showed more delayed response to Dex administration, and an increase in their content was observed only at higher doses (2.5 and 10 mg/kg) and only on 7–10 days after its administration, apparently, mainly due to an increase in heparan sulfate content. Conclusion. In general, the effect of a single injection of Dex on the transcriptional activity of GR, proteoglycan core proteins and heparan sulfate metabolism-involved genes were short-termed, and the genes expression quickly returned to the normal levels. However, even a single use of Dex significantly increased the content of total as well as highly sulfated glycosaminoglycans in the mouse brain tissue, which can lead to the changes in the composition and structure of the brain tissue, as well as its functional characteristics.

Objective: To compare the effectiveness of 6-hour normothermic autoperfusion of a heart graft ex vivo with pharmaco-cold preservation using Bretschneider's solution (Custodiol, Dr Franz Köhler Chemie GmbH, Bensheim, Germany).Methods: Landrace pigs weighing 50 ± 5 kg and aged 4–5 months (n = 10) were selected as a model for a series of acute experiments. Cardiopulmonary conditioning using autoperfusion was conducted for 6 hours on the experimental group (n = 5). On the other hand, the control group underwent a 6-hour pharmaco-cold preservation with Bretschneider solution to recover the heart's pumping function. Graft preservation effectiveness was evaluated by measuring hemodynamic parameters, heartbeat, and myocardial ischemia marker concentrations.Results: After reperfusion and isolation of the working cardiopulmonary complex, cardiac output was 0.63 [0.37; 0.8] L/min and 0.37 [0.23; 0.37] L/min in the experimental and control groups, respectively (P < .05). The levels of CPK-MB, LDH, troponin-I, and lactate in the coronary sinus blood was significantly higher in the control group.Conclusion: The study demonstrated significant benefits of normothermic autoperfusion in maintaining the morphofunctional status of the donor heart compared to pharmaco-cold preservation using Bretschneider's solution for 6 hours of ex vivo graft conditioning. Received 16 July 2023. Revised 8 September 2023. Accepted 11 September 2023. Funding: The study was carried out within the framework of project No. 23-25-10013 (agreement No. 23-25-10013 dated April 20, 2023 with the Russian Science Foundation, agreement No. р-52 dated April 3, 2023 with the Ministry of Science and Innovation Policy of the Novosibirsk Region). Conflict of interest: The authors declare no conflict of interest. Contribution of the authorsConception and study design: M.O. Zhulkov, D.A. Sirota, I.S. ZykovData collection and analysis: M.O. Zhulkov, A.R. Tarkova, I.S. Zykov, A.G. Makaev, A.V. Protopopov, M.N. Murtazaliev, F.Yu. Kosimov, N.A. Karmadonova, Ya.M. Smirnov, E.E. Kliver, A.M. Volkov, H.A. Agaeva, D.A. SirotaStatistical analysis: M.O. ZhulkovDrafting the article: M.O. ZhulkovCritical revision of the article: M.O. Zhulkov, D.A. Sirota, I.S. ZykovFinal approval of the version to be published: M.O. Zhulkov, A.R. Tarkova, I.S. Zykov, A.G. Makaev, A.V. Protopopov, M.N. Murtazaliev, F.Yu. Kosimov, N.A. Karmadonova, Ya.M. Smirnov, E.E. Kliver, A.M. Volkov, H.A. Agaeva, D.A. Sirota

Цель. Провести сравнительное исследование эффективности 6-часовой нормотермической аутоперфузии сердечного трансплантата ex vivo и фармакохолодовой консервации кустодиолом (Custodiol HTK, Dr Franz Köhler Chemie GmbH, Бенсхайм, Германия). Методы. В качестве модели для проведения серии острых экспериментов использовали свиней породы ландрас весом 50 ± 5 кг в возрасте 4–5 мес. (n = 10). В экспериментальной группе (n = 5) кондиционирование сердечно-легочного комплекса проводили методом аутоперфузии в течение 6 ч. В контрольной группе восстановление насосной функции сердца осуществляли после 6-часовой фармакохолодовой консервации кустодиолом. Оценивали эффективность консервации трансплантата путем измерения параметров гемодинамики, ударной работы сердца, концентрации маркеров ишемии миокарда. Результаты. После реперфузии и изоляции работающего сердечно-легочного комплекса сердечный выброс составил 0,63 [0,37; 0,80] и 0,37 [0,23; 0,37] л/мин в экспериментальной и контрольной группах соответственно (р < 0,05). Концентрация креатинфосфокиназы-МВ, лактатдегидрогеназы, тропонина I и лактата в оттекающей из коронарного синуса крови была в 2 раза выше в группе контроля. Заключение. Нормотермическая аутоперфузия показала значительное преимущество в сохранении морфофункционального статуса донорского сердца по сравнению с фармакохолодовой консервацией кустодиолом в течение 6 ч кондиционирования трансплантата ex vivo. Поступила в редакцию 16 июля 2023 г. Исправлена 8 сентября 2023 г. Принята к печати 11 сентября 2023 г. Финансирование Исследование выполнено в рамках проекта № 23-25-10013 (соглашение № 23-25-10013 от 20.04.2023 г. с Российским научным фондом, соглашение № р-52 от 03.04.2023 г. с Министерством науки и инновационной политики Новосибирской области). Конфликт интересов Авторы заявляют об отсутствии конфликта интересов. Вклад авторов Концепция и дизайн работы: М.О. Жульков, Д.А. Сирота, И.С. Зыков Сбор и анализ данных: все авторы Статистическая обработка данных: М.О. Жульков Написание статьи: М.О. Жульков Исправление статьи: М.О. Жульков, Д.А. Сирота, И.С. Зыков Утверждение окончательного варианта статьи: все авторы

Objective: to carry out a comparative study of the efficacy of a 6-hour normothermic ex vivo heart and lung autoperfusion and cold cardioplegia using Bretschneider’s solution (Custodiol ® , Germany). Materials and methods. Landrace pigs weighing 50 ± 5 kg at the age of 4–5 months (n = 10) were used as a model for a series of acute experiments. In the experimental group (n = 5), the cardiopulmonary complex was conditioned by autoperfusion for 6 hours. In the control group, the heart pumping function was restored after 6-hour cold cardioplegia using Bretschneider’s solution. The efficiency of graft preservation was assessed by measuring hemodynamic parameters, myocardial contractile function, and myocardial oxygen consumption. Results. After reperfusion and repeated isolation of the working cardiopulmonary complex, cardiac output was 0.63 [0.37; 0.8] L/min and 0.37 [0.23; 0.37] L/min in the experimental and control groups, respectively (p < 0.05). Indicators – global left ventricular stroke work index and preload recruitable stroke work – were significantly higher in the experimental group (p < 0.05). Conclusion. Normothermic autoperfusion is significantly more effective in preserving the morphofunctional status of a donor heart than static cold storage with Bretschneider solution for 6 hours.

Objective: to evaluate the technical feasibility as well as functional, metabolic and structural integrity of donor heart myocardium after 4 hours of direct intracoronary oxygen persufflation in an experiment. Materials and methods. Mini-pig siblings aged 3 months with a body weight of 23–36 kg were used as the experimental model. In the control group (n = 8), donor hearts were cold preserved by injecting 2 liters of Bretschneider cardioplegic solution (Custodiol®, Germany, HTK) into the aortic root. In the experimental group (n = 8), modified HTK solution (with 40 mg/L hyaluronidase added) was used to initiate cardioplegia, then moistened carbogen (95% O2, 5% CO2) was injected into the ascending aorta, maintaining 40–45 mm Hg aortic root pressure. The hearts were stored in an mHTK solution at 0–4 °С. After 3 hours of donor heart preservation, orthotopic heart transplantation (OHTx) was performed. In the post-transplant period, we studied central hemodynamic parameters, myocardial oxygen consumption, level of myocardial ischemia markers (troponin I, TnI; creatine phosphokinase-MB, CPKMB; lactate dehydrogenase, LDH), and histological signs of structural cellular injury. Results. Sixteen OHTx surgeries were performed during the study. At 120 minutes after restoration of spontaneous cardiac activity, cardiac output was 2.99 [4.85; 3.17] L/min and 2.48 [2.04; 2.92] L/min (p > 0.05) in the control and experimental groups, respectively. Changes in LDH, TnI and lactate levels in the blood flowing from the coronary sinus were significantly higher in the early reperfusion period. However, there was no statistically significant difference between the groups (p > 0.05). Myocardial oxygen consumption in the control and experimental groups was 8.2 [7.35; 9.35] ml-O2/min/100 g and 7.7 [6.75; 10.12] ml-O2/min/100 g, respectively (p > 0.05). Morphological examinations also showed no significant myocardial ischemia injury in the persufflation group compared to the control group. Conclusion. The experiment showed the technical feasibility and safety of direct intracoronary oxygen persufflation for 4 hours at the ex vivo donor heart conditioning stage. At the same time, experimental data showed no significant advantages of coronary persufflation over the standard protocol of cold preservation of donor heart with Bretschneider cardioplegic solution.

качество жизни пациентов с ишемической

Undifferentiated pleomorphic sarcoma is a high-grade malignant tumour, accounting for one-third of all primary cardiac sarcomas. This paper describes a case of undifferentiated pleomorphic sarcoma in an infant using detailed morphological characterisation, immunohistochemical examination and a brief literature review. Taken together, these data will be useful not only for practicing pathologists but also for researchers of other biomedical fields for the development of procedures for differential diagnoses, investigation of the pathogenesis and development of therapeutic approaches for undifferentiated pleomorphic sarcoma.Received 4 February 2019. Revised 31 March 2020. Accepted 9 April 2020.Funding: The study did not have sponsorship.Conflict of interest: Authors declare no conflict of interest.Author contributionsDrafting the article: I.S. Murashov, E.E. KliverLiterature review: V.E. Kliver, T.A. AgeevaIllustrations: V.E. Kliver, A.M. VolkovCritical revision of the article: I.S. Murashov, E.E. KliverFinal approval of the version to be published: I.S. Murashov, V.E. Kliver, T.A. Ageeva, A.M. Volkov, E.E. Kliver

AIM:to investigate diagnostically significant for atherosclerotic plaques (ASP) of various types parameters of activity of matrix metalloproteinases (MMP-3, MMP-7, MMP-9) in homogenates, as well as tissue expression of MMP-2, MMP-9 and collagen type IV.MATERIALS AND METHODS:We included in this study 54 men with coronary atherosclerosis without acute coronary syndrome who underwent coronary artery bypass surgery with endarterectomy. In the obtained samples we determined levels of MMP-3, MMP-7, and MMP-9 (by enzyme immunoassay), as well as tissue expression of antibodies to MMP-2, MMP-9 and collagen type IV.RESULTS:In unstable plaques we observed increased activity of MMP-7 and MMP-9, significant increase of tissue expression of MMP-2 and MMP-9, and decreased expression of type IV collagen. Of three types of unstable ASP the highest tissue expression of MMP-9 was found in plaques of lipid type compared with plaques of necrotic and inflammatory-erosive types. Expression of type IV collagen predominated in plaques of necrotic type.CONCLUSION:The data obtained allows us to speak about tissue expression of collagen as the marker of fibrous cap stability; the presence of metalloproteinases in necrotic detritus, collagen fibers, and cellular elements can characterize an ASP as unstable or being in the transitional structural state. The immunohistochemical method helps to detect structural elements that characterize instability in various types of ASP.

Aim. The study was designed to focus on the evaluation of in vitro implantation of a new transcatheter mitral bioprosthesis. Methods. A prototype of the first domestic self-expanding transcatheter bioprosthesis “Solertis” was tested by implanting it in the position of a native mitral valve of isolated pig heart by using transatrial access. Results. A correct orientation of the atrial and ventricular elements of the bioprosthesis and reliable circular coverage/adaptation of the annular part of the stent, which provide stable fixation of the prosthesis in a mitral position without left ventricular outflow tract obstruction, were determined. The function of the prosthesis during saline load test was adequate and without paraprosthetic regurgitation. Conclusion. The prototype of “Solertis” self-expanding transcatheter bioprosthesis demonstrated its efficiency for the native mitral valve replacement in vitro. The study results allow for proceeding to the next stage of preclinical testing—in vivo investigation.Received 5 December 2017. Accepted 20 December 2017. Published online 28 December 2017.Funding: The study was carried out with the support of a grant of the Russian Science Foundation (16-15-10315).Conflict of interest: The authors declare no conflict of interest.Author contributionsConception and study design: I.Yu. ZhuravlevaData collection and analysis: D.P. DemidovDrafting the article: R.M. SharifulinArticle editing: A.V. Bogachev-Prokophiev, A.M. KaraskovFinal approval of the version to be published: A.V. Bogachev-Prokophiev, I.Yu. Zhuravleva, R.M. Sharifulin, D.P. Demidov, A.M. Karaskov

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 performed a complex morphological study of samples of different types of unstable atherosclerotic plaques obtained from 33 men with occlusive coronary atherosclerosis, who underwent coronary artery endarterectomy during coronary artery bypass surgery. In the samples, expression of MMP-2 and MMP-9, collagen IV, CD31, CD34, factor VIII, and actin of smooth muscle cells was evaluated by morphometric and immunohistochemical methods. The maximum expression of MMP-9 was found in unstable plaques of the lipid type, where it 1.4- and 1.24-fold surpassed the corresponding levels in plaques of the inflammatory-erosive and degenerative-necrotic types. Unstable plaques of the degenerative-necrotic type are characterized by the most intensive expression of collagen IV in comparison with plaques of the inflammatory-erosive and lipid types (by 2.8 and 2.2 times, respectively). The maximum neovascularization was detected in inflammatory-erosive plaques, which was confirmed by enhanced expression of CD31 and CD34 markers in comparison with plaques of the lipid (by 7.6 and 18.95 times, respectively) and degenerative-necrotic (by 31.1 and 39.8 times) types.

Objective. The study was designed to assess the morphology and structural changes in the walls of the left subclavian artery in neonates and infants with coarctation and aortic arch hypoplasia.Methods. The study included 27 patients with hypoplasia of the aortic arch at the age of 64 (27; 89) days, average body weight of 3.6±1.1 (from 1.8 to 6.9 kg), who were operated at the Center of Pediatric Surgery of Academician Ye. Meshalkin Research Institute of Circulation Pathology in the period from 2013 to 2014. All patients underwent off-pump surgery of hypoplasia of the aortic arch by using modified reverse plasty with a patch from the left subclavian artery. The patch was taken intraoperatively to determine the ratio of elastin and collagen. The results were compared with those of the control group.Results. Significant differences were found in the content of collagen and elastic fibers in patients with aortic arch hypoplasia. Patients with hypoplasia had a significantly higher content of thin collagen and a lower content of elastic fibers in the wall of the subclavian artery.Conclusion. The morphology of the subclavian artery in children with aortic arch hypoplasia is characterized by an increase of collagen and a decrease of elastic fibers due to the proliferation of smooth muscle cells, myofibroblasts, fibroblasts and the change in their relationship. These features determine the changes in elastic characteristics of the vascular wall, i.e. increased rigidity.