Physical Parameters of Polymer Composite Materials Created on the Basis of Low and High Molecular Weight Rubbers

ABSTRACT. The theoretical foundations of the structural and mechanical behavior of filled three-dimensional cross-linked elastomers are supplemented. Numerical experiments are carried out, based on the data of numerical experiments, three dimensional cross linked, filled with dispersed particles frost-resistant elastomers based on low and high molecular weight rubbers are developed. Theoretical and experimental data are compared and their good convergence is shown. Comparison of the physical parameters of the composites created by the authors on the basis of low and high molecular weight rubbers showed that the deformation characteristics of the composite based on high molecular weight rubbers are many times superior to composites based on low molecular weight, as well as their glass transition temperature is also very different. The created composites are recommended as a structural material in relation to the engineering problem of creating wear-resistant parts and components of road and air transport operated in a wide temperature range, including the Far North and the Arctic. &nbsp

Dependence of mechanical characteristics from composition and structure and optimization of mechanical fracture energy of polymer composite material based on high-molecular rubbers

By means of numerical experiment the authors investigate dependence of conventional rupturing stress and mechanical fracture energy at uniaxial tension from fractional composition of dispersed filler, plasticizer volume fraction in polymer binder, effective density of transverse bonds, applied to development of covering for different purposes and with advanced service life in temperature range from 223 to 323 K. They compare mechanical characteristics of polymer composite materials (PCMs) based on high- and low-molecular rubbers. It was shown that rupturing stress of high-molecular rubber-based PCM is of a higher magnitude than the stress of low-molecular rubber-based one at almost invariable rupturing deformation. Numerical simulation by variation of composition parameters and molecular structure enables evaluation of its maximum fracture energy which is 1000 times higher than mechanical fracture energy of similar composites based on low-molecular rubbers

Биохимические маркеры метастазирования в кости

Bone metastasis is one of the most frequent and dangerous complications of malignant tumors. The last years, achievements in the study of bone remodeling mechanisms promoted the search of sensitive and specific criteria reflecting the intensity of osteolysis and osteosynthesis in bone metastatic lesions. The most informative and clinically valid biochemical markers of bone formation and resorption are characterized in this review. The data on their possible implications in diagnostics, monitoring and prognosis of skeletal lesions by various malignant tumors are presented. The attention to biochemical markers of bone remodeling as noninvasive methods for oncologic patients examination is gradually increasing with adoption of modern laboratory technologies to clinical practice. The last years, publications suggest the possibility of their use both for monitoring, prognosis and early diagnostics of bone metastasis. We present the results of our own investigation of serum C-telopeptide of type I collagen (СТX) as bone resorption marker and bone-specific alkaline phosphatase (BAP) as formation marker in 238 breast cancer patients using ELISA methods. The elevation of studied biochemical parameters in breast cancer patients was significantly associated with the extent of skeletal metastases (р < 0.02–0.00001), pathological fractures (р < 0.005–0.0001) and the severity of pain (р < 0.01–0.00002). Elevated rate of bone turnover was associated with reduced overall survival of breast cancer patients. The significant difference of overall survival estimated on a base of cut-off values of CTX (0.74 ng/ml) and BAP (43.7 IU/L) was found both in the groups of breast cancer patients with and without bone metastases. Serum СТХ and BAP are of value in monitoring and predicting the status of breast cancer bone metastases.Метастазирование в кости – одно из наиболее частых и опасных осложнений злокачественных опухолей. Достижения последних лет в изучении молекулярных механизмов костного ремоделирования способствовали поиску чувствительных и специфичных критериев, отражающих интенсивность процессов остеолиза и остеосинтеза при метастатическом поражении скелета. В обзоре охарактеризованы наиболее информативные и получившие внедрение в клиническую практику биохимические маркеры формирования и резорбции костной ткани. Приведены данные об их возможном использовании в диагностике, мониторинге и прогнозе поражения скелета злокачественными опухолями разной локализации. Интерес к биохимическим маркерам костного ремоделирования как неинвазивным методам обследования онкологических больных усиливается по мере внедрения в клиническую практику современных лабораторных технологий. Работы последних лет свидетельствуют о возможности их применения не только в целях мониторинга и прогноза, но и для проведения ранней диагностики метастазов в костях. Представлены результаты собственных исследований ключевых биохимических маркеров остеолиза (С-концевого телопептида коллагена I типа (СТХ)) и остеосинтеза (костной щелочной фосфатазы (КЩФ)) на основе иммуноферментного анализа в сыворотке крови 238 больных раком молочной железы (РМЖ). Установлена зависимость секреции КЩФ и СТХ от клинических проявлений метастазов в костях: достоверное увеличение их уровней зависело от степени поражения скелета (р < 0,02–0,00001), наличия патологического перелома (р < 0,005–0,0001) и выраженности болевого синдрома (р < 0,01–0,00002). Усиление интенсивности процессов костного ремоделирования было связано с достоверным уменьшением показателей общей выживаемости больных РМЖ. Высокодостоверные различия общей 5-летней выживаемости, рассчитанной с учетом пороговых уровней СТХ (0,74 нг/мл) и КЩФ (43,7 Ед/л), были получены для больных РМЖ как с исходными костными метастазами, так и без поражения скелета. СТХ и КЩФ являются биохимическими критериями, имеющими самостоятельное значение в мониторинге и прогнозе метастатического поражения скелета у больных РМЖ

Analysis of blood plasma cytokine profile in healthy residents of the Republic of Guinea

The cytokine system is a large group of humoral factors  produced by immune cells and involved in the  pathogenesis of most  human diseases.  To assess the  significance of changes  in cytokines/chemokines under  pathological conditions, appropriate reference values are required for healthy  people.  As known  from existing literature, most studies of various cytokine/chemokine concentrations in blood plasma were performed in healthy  subjects from Western Europe and North America.  Certain inter-population differences are known, with  respect  to production of distinct cytokines in different  racial  and  national groups.  Only  single studies concern normal levels of distinct cytokines in blood  plasma  of healthy  African  residents. The purpose  of this study was to determine the blood plasma cytokine profile in healthy  residents of the Republic of Guinea (RG), and to establish normal cytokine values.We have  examined 24  healthy  RG  residents and  23  residents of St.  Petersburg. Concentrations  of 40 cytokines/chemokines were determined in blood plasma.  The study was performed using multiplex analysis by xMAP technology.The  following  cytokine/chemokine levels  were  significantly   increased in  the  blood  plasma  of the  RG residents: IFNγ, IL-2, IL-4, IL-6, IL-10, TNFα, CCL1/I-309, CCL3/MIP-1α, CCL7/MCP-3, CCL17/ TARC, CCL19/MIP-3β,  CCL20/MIP-3α,  CCL21/6Ckine, CXCL2/Gro-β,  CXCL5/ENA-78, CXCL6/ GCP-2, CXCL9/MiG, CX3CL1/Fractalkine (р < 0.001).  For  the  CCL8/MCP-2, CCL22/MDC, CXCL1/ Gro-α and CXCL12/SDF-1α+β chemokines a trend for increased concentration was revealed, in comparison with residents of St. Petersburg (р < 0.05). Moreover, the levels of CCL23/MPIF-1 and MIF were significantly lower (р < 0.0001) in the RG residents. There was a tendency for decreased levels (р < 0.05) for CCL2/MCP-1 and CCL24/Eotaxin-2 chemokines in blood plasma taken from RG residents. There were no differences in levels of cytokines/chemokines for the studied  groups: GM-CSF, IL-1β, IL-16, CCL11/Eotaxin, CCL13/MCP-4, CCL15/Leukotactin-1, CCL25/TECK, CCL26/Eotaxin-3, CCL27/CTACK, CXCL8/IL-8, CXCL10/IP-10, CXCL11/I-TAC, CXCL13/BCA, and  CXCL16/SCYB16. Hence, this study  has presented for the  first time the normal limits for a wide range of cytokines/chemokines in blood plasma  of the African inhabitants. Interpopulation differences were found, including those  for constitutive chemokines. Different levels of CCL19/ MIP-3β and CCL21/6Ckine chemokines (the CCR7 receptor ligands) for the two populations may indirectly indicate the physiological features of T-cell maturation. Increased levels of CXCR2 receptor ligands in the blood plasma  of Guineans, i.e.,  CXCL2/Gro-β, CXCL5/ENA-78 and  CXCL6/GCP-2, may be due  to additional function of these chemokines as ligands for atypical DARC chemokine receptor, which neutralizes chemokines from the blood flow, whereas 95% of West Africans have mutations in the DARC gene and do not express this receptor. Increased levels of proinflammatory IL-6  and TNFα cytokines, and chemokine CCL20/MIP-3α in blood plasma  from RG  residents may suggest inflammatory processes  in the liver, since 100% of the examined Guineans had antibodies against the hepatitis A virus, 48% had antibodies to hepatitis B virus (anti-HBs), and 12% had antibodies against hepatitis C virus. In summary, the differences in cytokine/chemokine level may be related  to specific environment, circulation of infectious diseases, composition of intestinal, skin and mucosal microbiota, as well as distinct genetic  features

Content of certain cytokines and chemokines in blood ofpatients with chronic hepatitis B in the early stages of liver fibrosis

Hepatitis B is an infectious viral disease in which damage or destruction of liver tissue occurs, and which can turn into a chronic form. In chronic hepatitis B (CHB), hepatocytes are replaced by connective tissue as they die, resulting in fibrosis, and then cirrhosis of the liver. Early diagnosis of liver fibrosis is an urgent task in the development of CHB. Already at this stage of the disease, the immune system is activated, which plays a leading role in liver damage in CHB. The main regulators of immune processes are cytokines, which mediate intercellular interactions. A separate group of cytokines are chemokines — proteins of cell migration. In CHB, they are responsible for infiltration of liver tissue by activated white blood cells. Cytokines and chemokines are active participants in fibrogenesis, so they can serve as biomarkers for the development of liver fibrosis, including in the early stages. The purpose of this study was to analyze the content of certain cytokines/chemokines in the peripheral blood of patients with CHB in order to search for potential biomarkers of the initial stages of liver fibrosis. The study included 30 patients with a confirmed diagnosis of CHB with stages of liver fibrosis F0-F1 on the Metavir scale, 36 patients with a diagnosis of chronic hepatitis C (F0-F1) and 37 conditionally healthy individuals as a control group. Concentrations of the following cytokines/chemokines were determined: IFNγ, TNFα, CCL2/MCP-1, CCL8/MCP-2, CCL20/MIP-3α, CXCL9/MIG, CXCL10/IP-10, CXCL11/I-TAC by multiplex analysis using xMAP technology (Luminex, USA). As a result of the study, it was found that in patients with CHB, the plasma content of cytokine TNFα and chemokines CCL2/MCP-1, CXCL9/MIG and CXCL10/IP-10 was increased, and the chemokine CCL8/MCP-2 was reduced, which indicates the possibility of using these cytokines/chemokines as biomarkers of liver damage in CHB. In the examined group of patients with CHB, there was no dependence of the concentrations of cytokines and chemokines in the blood plasma on the viral load, which may be explained by its low level. For plasma cytokines in patients with CHB, correlations were found between TNFα and CCL2/MCP-1 and CCL8/MCP-2 chemokines , which was not observed in the control group. At the same time, in the control group, a correlation was found between the content of TNFα and the chemokine CXCL9/MIG, which was not detected in the group of patients. For both groups, a correlation was found between the content of CXCL9/MIG and CXCL10/IP-10 chemokines. Based on the study data, an algorithm has been developed that allows us to establish chronic hepatitis B or chronic hepatitis C as the cause of the initial form of fibrosis F0-F1 in terms of the content of cytokines IFNγ, CCL2/MCP-1 and CCL8/MCP-2 in blood plasma with a diagnostic efficiency of 89.4%

Efficacy of genetically engineered biological agents in the treatment of uveitis associated with rheumatic diseases in children

The efficiency of incorporating genetically engineered biological agents (GEBAs) into a combination treatment regimen for rheumatic diseases (RD) (juvenile idiopathic arthritis, Behcet's disease) in relation to associated uveitis of varying severity was studied in 92 children aged 2 to 17 years. The follow-up lasted 1.5 to 49 months. Twenty-three patients took consecutively 2 to 5 GEBAs. When infliximab was used, remission of uveitis occurred in 21% of 38 children and the disease activity and/or recurrence rates reduced in an additional 21%. These were in 45 and 38.6% of 44 patients on adalimumab (ADA) and in 27.8 and 27.8% of 18 patients on abatacept, respectively. There was an association of the efficiency of therapy with the severity of uveitis at the start of treatment. The use of ADA induced a steady remission of panuveitis resistant to therapy with glucocorticoids and cyclosporine in both patients with Behcet's disease. One of 4 rituximab-treated patients achieved a steady remission. Tocilizumab therapy caused an exacerbation of uveitis in 1 patient. The postoperative period showed no inflammatory complications in most cases (37 operations, 26 eyes, 20 patients). No local adverse reactions were seen; systemic reactions occurred in 14% of the patients, this caused GEBAs to be discontinued in 7%. There is evidence for a need for further investigations into the efficacy of GEBAs in RD-associated uveitis in children in order to define success criteria, differentiated indications, and therapy regimens

Clinical and immunological characteristics of patients with chronic hepatitis C during antiviral therapy in interferon-free regimen

Aim. To study the biomarkers of liver inflammation that occur during antiviral therapy in the interferon-free regimen. Methods. 14 patients were examined during antiviral therapy of chronic viral hepatitis C genotype 1. Treatment with dasabuvir, ombitasvir, paritaprevir and ritonavir for 12 weeks was received by 8 patients. Daklatasvir and asunaprevir was administered to 6 patients for 24 weeks. 11 patients had the concentrations of cytokines/chemokines (TNFα, CCL2/MCP-1, CCL20/MIP-3α, CXCL9/MIG, CXCL10/IP-10, CXCL11/ITAC) measured in the blood plasma by multiplex analysis. In six patients, the content of CXCR3+ and CCR6+ receptors in different subpopulations of lymphocytes was determined by flow cytofluorimetry. Patients were divided into 2 groups: without liver fibrosis and with severe fibrosis. Results. 100% demonstrated virologic response. In both groups, significant reduction of CXCL10/IP-10 concentration was found in the patients at the end of treatment compared to pre-therapy (p=0.025 and 0.00015, respectively). In the first group a tendency to increase of the relative content of T-lymphocytes (p=0.065) was observed, and in the second group, a significant increase of the relative content of TNKCCR6+ (p=0.02) was observed. Conclusion. Chemokine CXCL10/IP-10 is a biomarker characterizing the decrease of liver inflammation during therapy and not depending on the degree of liver fibrosis. The tendency to increase of the relative content of T lymphocytes in the first group and a significant increase in TNKCCR6+ cells during treatment in the second group may play an important role in eliminating hepatitis C virus

Ингибин В при стромально-клеточных опухолях яичников

Background. Tumors of stroma of the sex cord include a family of tumors that are diverse in structure and biological characteristics, including hormone-active ovarian tumors, such as granulosa cell tumor (GCT) of the ovary and a tumor from Sertoli–Leydig cells. For these types of tumors, of particular importance is the analysis of biochemical markers, among which the most promising is inhibin B.The objective of the study. Comparative analysis of inhibin B levels in the blood serum of patients with stromal cell tumors and other types malignancies.Materials and methods. 64 patients with primary ovarian tumors were examined: 31 – GCT of the ovary, 16 – tumors from Sertoli–Leydig cells, 17 – adenocarcinomas. Comparison group – 20 patients with malignant tumors of other localizations, control – 74 healthy women and 37 patients with benign ovarian tumors. Inhibin B was determined in blood serum using the standardized Inhibin B Gen II ELISA (Beckman Coulter, USA) immunoassay.Results. The analysis of inhibin B levels in last days of the luteal phase, show an increase of marker level in patients with GCT and tumors from Sertoli–Leydig cells, while in ovarian adenocarcinomas and malignant tumors of other locations inhibin B secretion doesn’t differ from the control. The sensitivity of inhibin B in diagnostics of GCT was 93.5 %, in tumor from Sertoli–Leydig cells – 81.3 % with specificity – 100 %.Conclusion. Inhibin B is an effective biomarker of GCT and ovarian tumors from Sertoli–Leydig cells, which results must be interpreted according the functional state of the ovaries.Введение. К опухолям стромы полового тяжа относится семейство разных по строению и биологическим особенностям опухолей, включая гормонально-активные опухоли яичников, такие как гранулезоклеточная опухоль яичника (ГКОЯ) и опухоль яичника из клеток Сертоли–Лейдига. Для данных типов опухолей особенное значение имеет анализ биохимических маркеров, к одним из самых перспективных относится ингибин B.Цель исследования – сравнительный анализ сывороточных уровней ингибина В у больных со стромально-клеточными опухолями и другими типами злокачественных новообразований.Материалы и методы. Обследованы 64 женщины с первичными опухолями яичников (31 – ГКОЯ, 16 – опухоль из клеток Сертоли–Лейдига, 17 – аденокарцинома). Группу сравнения составили 20 больных со злокачественными опухолями других локализаций, контрольную группу – 74 женщины без онкологических заболеваний и 37 больных с доброкачественными неоплазиями яичников. Определение уровня ингибина B в сыворотке крови проводили с использованием стандартизованного иммуноферментного набора Inhibin B Gen II ELISA (Beckman Coulter, США).Результаты. При анализе уровня ингибина В выявлено его повышение при ГКОЯ и опухолях из клеток Сертоли–Лейдига, тогда как при аденокарциномах яичника и злокачественных опухолях других локализаций секреция ингибина B не отличалась от таковой в контрольной группе. Чувствительность ингибина В в диагностике ГКОЯ составила 93,5 %, при опухоли из клеток Сертоли–Лейдига – 81,3 % при специфичности по контролю 100 %.Заключение. Ингибин B – высокоэффективный биомаркер ГКОЯ и опухолей яичников из клеток Сертоли–Лейдига, при анализе уровня которого следует учитывать функциональный статус яичников

STUDY OF THE EFFICIENCY AND SAFETY OF MYCOPHENOLATE MOFETIL THERAPY IN PATIENTSWITH SYSTEMIC SCLERODERMA

Interstitial lung disease (ILD) is one of the major causes of death in systemic scleroderma (SSD). Treatment of these patients remains difficult and controversial. Mycophenolate mofetil (MPM) has been in vitro shown to inhibit overproduction of type I collagen and hence may be effective against SSD. Objective: to study the efficiency and safety of MPM therapy in patients with SSD and clinically relevant ILD in an open-label prospective study. Subjects and methods. Ten patients with SSD (7 and 3 with its diffuse and limited forms, respectively) and ILD were given MPM in combination with glucocorticoids (mean daily dose was 10+4 mg). The mean MPM therapy duration was 11.4+1.3 months. The Rodnan total skin thickness score, flexion index, forced vital capacity (FVC), diffusing capacity of the lung for carbon monoxide (DLCO), and European Scleroderma Study Group (EScSG) activity index were estimated and a 6-minute walk test (6MWT) was carried out before and after MPM therapy. Results. After therapy, the whole group showed a significant reduction in skin scores from 12.9+9.8 to 5.6+3.2 (p=0.036) and EScSG from 3.9+1.4 to 2.25+1.03 (p=0.015) and an increase in exercise tolerance from 446+155 to 535+78 m (p=0.03) as evidenced by 6MWT. The degree of flexion contractures decreased from 15+21 to 3.7+11.3 mm (p>0.05). FVC (77.8+18.7% versus 73.8+11.3%) and DLCO (45+14.4% versus 42+16.4%) were significantly unchanged. A 10% or more clinically significant fall was noted in FVC and DLCO in 3 and 1 patients, respectively. In the remaining patients, the lung functional test results remained stable. MPM tolerability was satisfactory. All the patients completed their course of treatment. Conclusion. Stabilization of lung function with higher exercise tolerance and significantly reduced skin density allow therapy with MPM in combination with low-dose glucocorticoids to be regarded as an effective and well-tolerated treatment in patients with ILD in the presence of SS

Биохимические показатели в сыворотке крови больных нейроэндокринными опухолями с карциноидным синдромом

Introduction. Carcinoid syndrome is the most common functional syndrome in patients with neuroendocrine tumors. More than 40 biochemical factors are responsible for the manifestation of carcinoid syndrome, among which serotonin is the most important. The study of biochemical markers of carcinoid syndrome and associated carcinoid heart disease is an important aim of laboratory examination in neuroendocrine tumors patients.Aim. Analysis of levels and diagnostic efficiency evaluation of chromogranin A (CgA), serotonin, pro-brain natriuretic peptide (proBNP) and platelet-derived growth factor (PDGF-BB) in the blood serum of neuroendocrine tumors patients with various clinical manifestations, including carcinoid syndrome and carcinoid heart disease.Materials and methods. 66 patients with neuroendocrine tumors of various localizations were examined (pancreas – 24 cases, small intestine – 21, large intestine – 6, lungs – 10, unkown primary focus – 5). 38 patients had liver metastases. In 43 patients, a clinic of carcinoid syndrome was observed, 16 had signs of carcinoid heart disease. The control group consisted of 30 practically healthy people. Serum levels of CgA, serotonin, and PDGF-BB were determined by enzyme immunoassay in microplate format: Chromogranin A NEOLISA (Eurodiagnostica, Sweden), Serotonin ELISA (IBL, German), and PDGF-BB ELISA Kit (Invitrogen, USA). The proBNP analysis was performed on a Cobas e601 automated analyzer (Roche, Switzerland).Results. In carcinoid syndrome, the medians of CgA, serotonin, and proBNP were the highest, differing statistically significantly from the control group. In patients with G3 tumors, the median PDGF-BB was statistically significantly higher than in controls, in contrast to G1 and G2. The highest diagnostic sensitivity in the general neuroendocrine tumors group was in CgA – 63.6 %, with a specificity of 100 %. In patients with carcinoid syndrome, the highest diagnostic sensitivity was characteristic of serotonin and chromogranin A (79 %), while in patients with CAD clinic, proBNP had the highest sensitivity – 93.8 %.Conclusion. The study revealed the high efficiency of СgA, with the highest sensitivity in common forms and tumors with high biological activity. Serotonin can be used in the diagnosis of carcinoid syndrome, associated with cardiofibrosis development. Pro-brain natriuretic peptide is a highly sensitive and specific marker of carcinoid heart disease. The highest levels of PDGF-BB are associated with a high grade of neuroendocrine tumors malignancy.Введение. Карциноидный синдром является наиболее частым функциональным синдромом у пациентов с нейроэндокринными опухолями. За манифестацию карциноидного синдрома отвечают более 40 биохимических факторов, среди которых наибольшее значение имеет серотонин. Исследование биохимических маркеров карциноидного синдрома и ассоциированной с ним карциноидной болезни сердца является актуальной задачей лабораторного обследования больных нейроэндокринными опухолями.Цель исследования – анализ уровней и оценка диагностической эффективности хромогранина А (ХгА), серотонина, мозгового натрийуретического пропетида (proBNP) и тромбоцитарного фактора роста (PDGF-BB) в сыворотке крови больных нейроэндокринными опухолями с различной клинической манифестацией, включая карциноидные синдром и болезнь сердца.Материалы и методы. Обследованы 66 больных нейроэндокринными опухолями различных локализаций (поджелудочная железа – 24 случая, тонкая кишка – 21, толстая кишка – 6, легкие – 10, невыявленный первичный очаг – 5). У 38 пациентов обнаружены метастазы в печени. У 43 больных отмечены клинические проявления карционидного синдрома, 16 имели признаки карциноидной болезни сердца. Контрольная группа представлена 30 практически здоровыми донорами. Уровни ХгА, cеротонина и PDGF-BB в сыворотке крови определяли с помощью иммуноферментного метода в плашечном формате с использованием тест-систем Chromogranin A NEOLISA (Eurodiagnostica, Швеция), Serotonin ELISA (IBL, Германия) и PDGF-BB ELISA Kit (Invitrogen, США). Анализ proBNP проводили на автоматическом анализаторе Cobas e601 (Roche, Швейцария).Результаты. При карциноидном синдроме медианы уровней ХгА, серотонина и proBNP были наиболее высокими и статистически значимо отличались от соответствующих показателей контрольной группы. Медиана PDGF-BB статистически значимо выше у больных с опухолями G3, чем в группе контроля, в отличие от пациентов с опухолями G1 и G2. Наибольшая диагностическая чувствительность в общей группе нейроэндокринных опухолей отмечена для ХгА (63,6 %) при специфичности 100 %. При карциноидном синдроме наиболее высокая диагностическая чувствительность была характерна для серотонина и ХгА (79 %). У пациентов с клиническими признаками карциноидной болезни сердца отмечалась большая диагностическая чувствительность для proBNP (93,8 %).Заключение. Проведенное исследование свидетельствует о высокой эффективности ХгА с наибольшей чувствительностью при распространенных формах и опухолях с высокой биологической активностью. Серотонин является чувствительным маркером карциноидного синдрома, ассоциированным с развитием кардиофиброза. Мозговой натрийуретический пропетид – высокочувствительный и специфичный маркер карциноидной болезни сердца. Наиболее высокие уровни PDGF-BB ассоциированы с большой степенью злокачественности нейроэндокринных опухолей