Browsing by Author "Stankovic, Vesna (35741953100)"

The aim of this study was to examine phenotype status of smooth muscle cells in adult coarctation, their proliferation activity and presence of inflammation in this lesion. We used bioptic material taken from 8 children, in age of 3-10. The tissues were fixed in formalin and embedded in paraffin. Sections 5 micrometers thick were stained by DAKO LSAB+/HRP technique to identify alpha-smooth muscle actin-alpha-SMA, vimentin, desmin, myosin haevy chains-MHC, CD3, CD45, S-100 and Proliferating Cell Nuclear Antigen-PCNA. Our results show significant hypocellularity in subendothelium, especially at posterior wall of aorta, but we conclude that it wasn't due to inflammation, because there wasn't CD3 or CD45 immunoreactivity. These results don't match with literature data, which demonstrate cystic medial necrosis of the base of aortic coarctacion. On the other side, there is thickening in subendothelium with dense elastic fibers. Characteristics of media under this lesion are fragmentation, fenestration and reduplicated elastic lamelae, cysts with mukopolisaharids and dedifferentiation of smooth muscle cells, which summary shows destruction of media began in previous stage of neonatal coarctation.

The neonatal type of coarctation is characterized by the presence of the ductal sling and coarctational shelf placed proximally in relation to the ductal orifice. Those morphological features are not described in detail yet from immunohistochemical and transmission electron microscopy (TEM) aspects, so the aim of this study was to investigate the smooth muscle cells (SMCs) phenotype in aortic intimal thickening, presence of inflammatory cells and contents of intimal and medial, and adventitial connective tissue. We examined samples of coarctation segments excised at surgery after end-to-end anastomosis from 30 patients, ages from 14 days to three months, histochemicaly, immunocytochemically and by TEM. In all samples, it is noticed focal intimal thickening on the posterior aortic wall, with accumulation of SMCs, which show immunoreactivity on alpha-smooth muscle actin (α-SMA) and vimentin (but not on desmin) and also expressed proliferating cell nuclear antigen (PCNA) and S-100 protein. At TEM analysis, those SMCs show a fibroblast-like morphology, so their functions could be to proliferate and secrete extracellular matrix (ECM) components (a synthetic phenotype). In all studied samples of the coarctation, on the posterior wall, the immunocytochemical and TEM examination revealed the presence of SMCs of the synthetic phenotype. Results also showed an increase of the cell number in intima of this part of aortic wall, followed by proliferated SMCs in inner media and absence of inflammatory cells. This finding suggests that proliferation of the SMCs, their synthetic activity and increase of the cell number could lead to formation of the intimal thickening on the posterior wall. © 2019, Editura Academiei Romane. All rights reserved.

The neonatal type of coarctation is characterized by the presence of the ductal sling and coarctational shelf placed proximally in relation to the ductal orifice. Those morphological features are not described in detail yet from immunohistochemical and transmission electron microscopy (TEM) aspects, so the aim of this study was to investigate the smooth muscle cells (SMCs) phenotype in aortic intimal thickening, presence of inflammatory cells and contents of intimal and medial, and adventitial connective tissue. We examined samples of coarctation segments excised at surgery after end-to-end anastomosis from 30 patients, ages from 14 days to three months, histochemicaly, immunocytochemically and by TEM. In all samples, it is noticed focal intimal thickening on the posterior aortic wall, with accumulation of SMCs, which show immunoreactivity on alpha-smooth muscle actin (α-SMA) and vimentin (but not on desmin) and also expressed proliferating cell nuclear antigen (PCNA) and S-100 protein. At TEM analysis, those SMCs show a fibroblast-like morphology, so their functions could be to proliferate and secrete extracellular matrix (ECM) components (a synthetic phenotype). In all studied samples of the coarctation, on the posterior wall, the immunocytochemical and TEM examination revealed the presence of SMCs of the synthetic phenotype. Results also showed an increase of the cell number in intima of this part of aortic wall, followed by proliferated SMCs in inner media and absence of inflammatory cells. This finding suggests that proliferation of the SMCs, their synthetic activity and increase of the cell number could lead to formation of the intimal thickening on the posterior wall. © 2019, Editura Academiei Romane. All rights reserved.