No abstract

Atherosclerosis commonly affects the arteries harvested from patients 70 years of age or older. Saphenous vein grafts appear to maintain a higher patency rate after coronary artery bypass grafting in these subjects. The infiltration of macrophages is an early step in saphenous vein graft atherosclerosis; however, little is known regarding the underlying mechanisms of infiltration. The objective of the present report is to evaluate the presence of CD68-positive cells in the saphenous vein wall and correlate initial CD68-positive infiltration to specific clinical and biochemical parameters and the graft patency rate as estimated in patients undergoing coronary artery bypass grafting. A total of 309 patients were allocated into two groups: A1 patients, who were between 50 and 70 years of age, and A2 patients, who were 70 years or older at the time of vein harvesting. CD68 expression was evaluated by immunohistochemistry. There were no significant differences between A1 and A2 patients regarding macrophage expression within any of the analyzed vascular regions. Saphenous vein macrophages were never present in the tunica intima unless they were also expressed in the media or the adventitia. The patients with CD68-positive cells in the tunica intima had a significantly higher number of bypass stenoses when compared with the subjects who did not have CD68-positive cells in this layer. These findings suggest that the CD68-positive cells (those that have not yet developed into foam cells) present in the intima of saphenous vein grafts might serve as a very early marker of graft occlusion.

The endothelial integrity of radial artery grafts harvested by minimally invasive surgery is better preserved than in the grafts obtained by the conventional manner. This could play an important role in improving graft patency and might represent a preliminary condition of stable functioning in coronary arterial bypasses.

Introduction. Migration of the smooth muscle cells (SMCs) to the tunica media in the saphenous vein (SV) transplants is facilitated by matrix metalloproteinases (MMPs). The aim of this study was to identify any associations between expression of MMP-2 or endogenous tissue inhibitors (TIMP-2 and TIMP-3) in the SV segments and late failure of the SV grafts. Methods. Two hundred consecutive patients with a mean age of 63.1 ± 8.9 years who underwent primary isolated venous CABG were examined. Patients were retrospectively split into two subgroups, with the SV graft disease (SVGD (+); n = 47) or without it (SVGD (−); n = 153). In the SV segments, immunohistochemical analysis of the expression of the MMP-2, TIMP-2, and -3 was performed. Results. In the SVGD (+) patients, tissue expression of MMP-2 was stronger, whereas that of both TIMPs was weaker than in the SVGD (−) patients. In majority of the SV segments obtained from the SVGD (−) individuals, a balance in MMP and TIMP expressions was found, whereas an upregulation of MMP-2 expression was usually noted in the SVGD (+) subjects. Conclusion. The strong expression of MMP-2 accompanied by reduced immunostaining of both TIMPs is associated with the development of the SV graft disease and unfavorable CABG outcomes.

BackgroundVenous aortocoronary graft arterialization may precede a preterm occlusion in some coronary artery bypass grafting (CABG) patients. The aim of the present study was to identify ultrastructural variations in the saphenous vein wall that may have an impact on the development of venous graft disease in CABG patients.MethodsThe study involved 365 consecutive patients with a mean age of 62.9±9.4 years who underwent isolated CABG. The thickness and area of the whole venous wall, the tunica intima, the tunica media and the adventitia and the number and shape (length, thickness and length/thickness ratio) of the nuclei in the medial smooth muscle cells nuclei in the distal saphenous vein segments were evaluated by ultrastructural studies. Patients were followed up for 41 to 50 months (mean 45.1±5.1). Saphenous vein graft patency was assessed by follow-up coronary angiography. Logistic regression models were used to identify independent risk factors for late graft failure.ResultsIn 71 patients significant lesions in the saphenous vein grafts were observed. The whole venous wall thickness (437.5 µm vs. 405.5 µm), tunica media thickness (257.2 µm vs. 211.5 µm), whole venous wall area (2.23 mm2 vs. 2.02 mm2) and tunica media area (1.09 mm2 vs. 0.93 mm2) were significantly larger for this group of patients than for those without graft disease. In the latter group more elongated smooth muscle cell nuclei (higher length/thickness ratio) were found in the tunica media of the saphenous vein segments. Thickening of the saphenous vein tunica media and chunky smooth muscle cell nuclei were identified as independent risk factors for graft disease development.ConclusionsSaphenous vein tunica media hypertrophy (resulting in wall thickening) and chunky smooth muscle cell nuclei might predict the development of venous graft disease.

Suppressors of Cytokine Signaling (SOCS) inhibit Signal Transducers and Activators of Transcription (STATs) phosphorylation by binding and inhibiting Janus Kinases (JaKs). The aim of the present study was to evaluate the influence of glucocorticosteroids on the JaK/STAT signaling pathway in the leukocytes of nephrotic syndrome (NS) patients. The study group was composed of 34 steroid sensitive NS (SSNS) children and 20 steroid resistant NS (SRNS) subjects. Gene expression was assessed by real-time PCR using pre-designed human JaK/STAT PCR array. Protein expression was evaluated using ELISA assay (plasma concentration) and immunofluorescence (in situ protein expression). In SSNS children, the initial increased expression of JaK1, JaK2, JaK3, STAT1, STAT2, STAT6, TYK2, SOCS1, SOCS2, SOCS3, SOCS4 and SOCS5 was reduced back to the control limits. Similarly, in SRNS patients the increased levels of almost all mRNA expressions for the abovementioned genes were decreased, with the exceptions of SOCS3 and SOCS5 expressions. These mRNA expressions were still significantly increased and correlated with early unfavorable course of nephrotic syndrome in children. Plasma levels of SOCS3, SOCS5, IL-6 and IL-20 were significantly increased in SRNS subjects after six weeks of steroids medication compared to SSNS and control participants. We conclude that SOCS3 and SOCS5 increased mRNA expressions might predict initial resistance

The aim of this study was to assess the blood vessel density and maturity in the skin of adults with type 1 diabetes in relation to the presence of late neurovascular complications. We included 148 patients (87 men) with a median (interquartile range) age of 41 (31–49) and median diabetes duration of 21 (17–30) years. Microvessel (CD133, CD34, CD31 and von Willebrand factor) markers were evaluated by indirect immunohistochemistry assay in material from a skin biopsy. Diabetic retinopathy was diagnosed using direct ophthalmoscopy, and diabetic kidney disease was estimated in people with increased albuminuria and a 10-year duration of diabetes or evidence of diabetic retinopathy . Diabetic peripheral neuropathy diagnosis was based on Toronto definition, cardiac autonomic neuropathy on validated ProSciCard III program. Microvessel density, assessed by CD34 and CD133, was significantly higher in patients with cardiac autonomic neuropathy [160 (125–175) vs 121 (100–154)/1 mm2, p = 0.001 and 92 (83–104) vs 79 (63–92)/1 mm2, p = 0.007, respectively] and CD34 in patients with diabetic peripheral neuropathy [135 (106–168) vs 121 (95–145)/1 mm2, p = 0.018], as compared with subjects without complications. In multivariate logistic regression, density of CD34 and CD133 positive vessels was associated with presence of cardiac autonomic neuropathy [odds ratio 1.016 (95% confidence interval: 1.002–1.029), p = 0.019 and odds ratio 1.037 (95% confidence interval: 1.008–1.067), p = 0.011, respectively]. It was independent from age, sex, diabetes duration, smoking status, body mass index and HbA1c value. Density of CD34 positive vessels was also associated with diabetic peripheral neuropathy, independently from sex and diabetes duration [odds ratio 1.009 (95% confidence interval: 1.001–1.020), p = 0.037]. Skin microvessel density is increased in adults with clinical evidence of neurovascular complications of type 1 diabetes. This is associated with predominance of the vessels of low maturity.

Structural alterations in thymuses of female rats during the first 2 years of life were evaluated by morphometric analysis and, then, correlated with organization of epithelial cells in various thymic compartments, examined for their cytokeratin immunoreactivity. With an advancing age, the thymuses demonstrated morphological modifications related to maturation and senescence, the dynamics of which varied between particular thymic compartments, and involved subpopulations of thymic epithelial cells. In the entire period of life the most dynamic changes were found in the cortex while the medulla was demonstrated to be a rather "stable" region. Morphometric studies revealed a negative correlation between the volume of thymic cortex and medulla and age of rats and a linear, positive relationship between the volume of connective tissue compartment and age. Changes in organization of epithelial network in the medulla preceded those observed in the cortex. Decreased proliferative activity of subset of medullary cells, which probably represented a self-renewable population, was accompanied by alterations in the immunocytochemically characterized (cytokeratines) differentiation process. At the same period of life, hypertrophy and hyperplasia of superficial epithelial cells seems to functionally replace medullary cells. This process begins around 3rd month of life and expands on all thymic compartments. The first changes in the cortex appeared around 8th month and were connected with reduced cytokeratin immunoreactivity. The involution observed in older animals was preceded by age-related alterations in epithelial network pattern which, in the course of stable morphometric parameters (between 5th and 12th month), showed character of a structural and functional adaptation.