[Show abstract][Hide abstract] ABSTRACT: Objectives:
To evaluate if the prooxidant environment present in atherosclerotic plaque may oxidatively modify filtered albumin.
Fluorescein-5-maleimide labelled plasma samples and plaque extracts from 27 patients who had undergone carotid endarterectomy were analysed through nonreducing SDS-PAGE for albumin-Cys(34) oxidation. Furthermore, degree and pattern of S-thiolation in both circulating and plaque-filtered albumin were assayed.
Albumin filtered in the atherosclerotic plaque showed higher levels of Cys(34) oxidative modifications than the corresponding circulating form as well as different patterns of S-thiolation.
Data indicate that the circulating albumin, once filtered in plaque, undergoes Cys(34) oxidative modifications and demonstrate for the first time that albumin is a homocysteine and cysteinylglycine vehicle inside the plaque environment.
Full-text · Article · Mar 2014 · Oxidative Medicine and Cellular Longevity
[Show abstract][Hide abstract] ABSTRACT: Apolipoproteins are very heterogeneous protein family, implicated in plasma lipoprotein structural stabilization, lipid metabolism, inflammation, or immunity. Obtaining detailed information on apolipoprotein composition and structure may contribute to elucidating lipoprotein roles in atherogenesis and to developing new therapeutic strategies for the treatment of lipoprotein-associated disorders. This study aimed at developing a comprehensive method for characterizing the apolipoprotein component of plasma VLDL, LDL, and HDL fractions from patients undergoing carotid endarterectomy, by means of two-dimensional electrophoresis (2-DE) coupled with Mass Spectrometry analysis, useful for identifying potential markers of plaque presence and vulnerability. The adopted method allowed obtaining reproducible 2-DE maps of exchangeable apolipoproteins from VLDL, LDL, and HDL. Twenty-three protein isoforms were identified by peptide mass fingerprinting analysis. Differential proteomic analysis allowed for identifying increased levels of acute-phase serum amyloid A protein (AP SAA) in all lipoprotein fractions, especially in LDL from atherosclerotic patients. Results have been confirmed by western blotting analysis on each lipoprotein fraction using apo AI levels for data normalization. The higher levels of AP SAA found in patients suggest a role of LDL as AP SAA carrier into the subendothelial space of artery wall, where AP SAA accumulates and may exert noxious effects.
Full-text · Article · Dec 2013 · Oxidative Medicine and Cellular Longevity
[Show abstract][Hide abstract] ABSTRACT: Objectives:
Oxidative stress has been implicated in the outcome of atherosclerotic plaques. However, at present, no data are available neither on the degree of plaque protein sulfhydryl groups oxidation nor on its relationship with plaque vulnerability. We investigated the entity of protein-SH oxidative modifications, focusing on low molecular weight thiols adduction, in human carotid plaque extracts in relation to plaque stability/instability.
Plaque stability/instability was histologically assessed. The extent of protein-SH oxidative modifications was established by a differential proteomic approach on fluorescein-5-maleimide-labeled plaque extracts and corresponding plasma samples from 48 endarterectomized patients. The analysis on protein thiolation was performed by capillary zone electrophoresis.
We observed a higher protein-SH oxidation of both plasma-derived and topically expressed proteins in unstable plaques, partly due to higher levels of S-thiolation. Conversely, in plasma, none of the investigated parameters discriminated among patients with stable and unstable plaques.
Our results suggest the presence of a more pronounced oxidative environment in unstable plaques. Identifying specific oxidative modifications and understanding their effects on protein function could provide further insight into the relevance of oxidative stress in atherosclerosis.
Full-text · Article · Feb 2013 · Oxidative Medicine and Cellular Longevity
[Show abstract][Hide abstract] ABSTRACT: We report on a patient with a femoropopliteal bypass infected by Kytococcus sedentarius. Treatment consisted of resection of the infected prosthesis with homograft substitution and antibiotic therapy started postoperatively. At 6 months followup, the patient showed no signs of infection and results of laboratory findings were normal.
Preview · Article · Sep 2012 · The International journal of artificial organs
[Show abstract][Hide abstract] ABSTRACT: Thoracic endovascular aneurysm repair (TEVAR) is an appealing alternative to the standard surgical approach, but requires rigorous radiological follow-up. The cumulative radiation exposure (RE) of patients undergoing TEVAR-including pre-operative workup, the procedure and subsequent follow-up computed tomography (CT) imaging-has not previously been investigated.
From August 2003 to February 2011, 48 patients underwent TEVAR at our institution. Mean age was 66 ± 11 years, with 10 patients (21%) aged <60 years. Forty-one (85%) patients were male; 7 (15%) had urgent/emergent operation; 21 (44%) had undergone previous aortic surgery. Mean aortic diameter was 7.3 ± 2.1 cm. Intra-operative screening time and RE were reviewed, and typical institutional thoracic CT scan RE was calculated (17.8 mSv). Life expectancy of an age- and sex-matched population was estimated to assess the cumulative RE from recurrent CT follow-up.
The average screening time was 15.7 ± 11.4 min, with an RE of 11.3 ± 9 mSv. Obese patients had significantly higher RE during TEVAR (Pearson's coefficient = 0.388, P = 0.019). The RE dropped from 14.9 ± 9.4 mSv to 8.6 ± 7.9 mSv (P = 0.033) after a hybrid suite was established. Our institutional TEVAR protocol involves one pre-operative thoracoabdominal CT scan and three follow-up thoracic CT scans for the first year, with a yearly evaluation thereafter. The life expectancy of an age- and sex-matched population was 17 years. A patient adhering to our surveillance protocol would be subjected to an overall exposure of 89 mSv at 1 year and 161 mSv at 5 years, with a projected lifetime RE >350 mSv.
A 2-year RE exceeding the threshold of 100 mSv with a life expectancy >15 years can be estimated to lead to a lifetime risk increase in radiation-induced leukaemia and solid-tumour cancer >2.7%. The risks of cumulative RE especially in younger and/or obese patients must be balanced with the expected morbidity and mortality reduction in TEVAR versus traditional open repair, and the anticipated benefits of recurrent radiographic imaging.
No preview · Article · Jan 2012 · European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery
[Show abstract][Hide abstract] ABSTRACT: Several studies have evidenced variations in plasma glycosaminoglycans content in physiological and pathological conditions. In normal human plasma GAGs are present mainly as undersulfated chondroitin sulfate (CS). The aim of the present study was to evaluate possible correlations between plasma CS level/structure and the presence/typology of carotid atherosclerotic lesion. Plasma CS was purified from 46 control subjects and 47 patients undergoing carotid endarterectomy showing either a soft or a hard plaque. The concentration and structural characteristics of plasma CS were assessed by capillary electrophoresis of constituent unsaturated fluorophore-labeled disaccharides. Results showed that the concentration of total CS isomers was increased by 21.4% (P < 0.01) in plasma of patients, due to a significant increase of undersulfated CS. Consequently, in patients the plasma CS charge density was significantly reduced with respect to that of controls. After sorting for plaque typology, we found that patients with soft plaques and those with hard ones differently contribute to the observed changes. In plasma from patients with soft plaques, the increase in CS content was not associated with modifications of its sulfation pattern. On the contrary, the presence of hard plaques was associated with CS sulfation pattern modifications in presence of quite normal total CS isomers levels. These results suggest that the plasma CS content and structure could be related to the presence and the typology of atherosclerotic plaque and could provide a useful diagnostic tool, as well as information on the molecular mechanisms responsible for plaque instability.
[Show abstract][Hide abstract] ABSTRACT: In the last ten years the contribution of both vessel wall-derived tissue factor (TF) and platelets to atherosclerosis has been revisited. At the beginning of the 2000 a circulating blood-borne TF has been proposed to sustain coagulation activation and propagation on the edge of a growing thrombus. Concomitantly with the observation that platelets not only contribute to thrombus formation, but also take part to the onset of the atherosclerotic lesion, evidences have been provided that they express functionally active TF, making them able to trigger the coagulation cascade.
No preview · Article · Dec 2011 · Thrombosis Research
[Show abstract][Hide abstract] ABSTRACT: Le traitement chirurgical d’un anévrysme de l’aorte abdominale après pneumonectomie est un défi en raison de la fonction respiratoire altérée et des risques chirurgicaux accrus. Le traitement endovasculaire chez les patients anatomiquement adaptés à haut risque-chirurgical offre d’excellents résultats à court terme et assure une bonne protection contre le décès lié à l’anévrysme. Dans cet article, nous rapportons le traitement endovasculaire d’un anévrysme de l’aorte sous-rénale chez un patient ayant eu une pneumonectomie.
No preview · Article · May 2011 · Annales de Chirurgie Vasculaire
[Show abstract][Hide abstract] ABSTRACT: Surgical treatment of abdominal aortic aneurysm after previous pneumonectomy is a challenge because of the impaired respiratory function and increased surgical risks. Endovascular aneurysm repair in anatomically suited high-surgical-risk patients offers excellent short-term results and provides good protection from aneurysm-related death. In this article, we report a successful endovascular aneurysm repair of an infrarenal aortic aneurysm in a patient with past left pneumonectomy.
No preview · Article · Mar 2011 · Annals of Vascular Surgery
[Show abstract][Hide abstract] ABSTRACT: Iatrogenic acute type B dissection is a rare complication of intraaortic balloon pumping. Delayed visceral and spinal cord malperfusion can occur for distal progression of the dissection or relative hypotension. Cerebrospinal fluid drainage and percutaneous balloon fenestration provide a safe and effective method for managing ischemic complications.
No preview · Article · Dec 2009 · The Annals of thoracic surgery
[Show abstract][Hide abstract] ABSTRACT: Despite the evidence that both homocysteine and cysteine are important risk factors for vascular disease and atherosclerosis no information are reported about their effective amount in plaque and on the relationship with the other low molecular weight thiols.
We used capillary electrophoresis to measure thiols in both carotid plaque specimens and plasma samples from 37 patients undergoing carotid endarterectomy.
Pearson's correlation shows that intraplaque homocysteine, cysteine and cysteinylglycine levels are related to their plasma concentrations. The distribution of intraplaque GSH and Glu-Cys was higher than that of the same thiols in plasma, whereas the other thiols were significantly less prevalent in plaque than in plasma. Intraplaque haemoglobin and GSH levels were correlated, thus suggesting their common origin from erythrocytes lysis.
Data suggest that increased levels of intraplaque glutathione may induce important effects on plaque fate by perturbing the normal LMW thiol redox state.
No preview · Article · Mar 2009 · Clinical biochemistry
[Show abstract][Hide abstract] ABSTRACT: By using proteomics we isolated and identified proteins that were expressed/retained in stable and unstable human carotid artery atherosclerotic plaques.
The criteria for plaque instability were the presence of a thin fibrous cap or fissured cap covering the foamy or necrotic core, and the presence of overt, hemorrhagic, ulcerated or thrombotic plaques. Proteins were extracted from finely minced endarterectomy specimens (19 stable and 29 unstable plaques) and separated by two-dimensional gel electrophoresis. Coomassie Blue-stained gels were analysed using PD-Quest software.
A total of 57 distinct spots corresponding to 33 different proteins were identified by matrix assisted laser desorption/ionization mass spectrometry using the NCBI database. Most of the spots were present in both types of extracts, although significantly (p<0.05) differing in abundance between them. Compared to stable plaque, unstable ones showed reduced abundance of: protective enzymes SOD3 and GST, small heat shock proteins HSP27 and HSP20, annexin A10, and Rho GDI. In unstable plaques the more abundant proteins were: ferritin light subunit, SOD 2 and fibrinogen fragment D. For fibrinogen fragment D, the increased levels in unstable versus stable plaques was confirmed by Western blot analysis.
Since many of the differentially expressed proteins are known to have a functional role in inflammation and oxidative stress, we speculate that they may be involved in events relating to plaque stability.
[Show abstract][Hide abstract] ABSTRACT: Here we report a rare case of a 74-year-old man with a pseudoaneurysm of the anterior tibial artery and a concomitant arteriovenous fistula (AVF). The patient was admitted because of increasing pain following the formation of a large mass located in the anterior mid-portion of the calf after a moderate non-penetrating blunt trauma. A polytetrafluoroethylene-covered stent was placed over the origin of the pseudoaneurysm, with complete exclusion of the pseudoaneurysm and disappearance of the AVF. One year after the procedure the mass had completely disappeared and the vascular anatomy of the calf is well preserved.
Full-text · Article · Jun 2007 · Journal of Vascular Surgery
[Show abstract][Hide abstract] ABSTRACT: Chylothorax is a rare complication of adult cardiothoracic surgery that can affect the postoperative course as it can lead to respiratory insufficiency, protein loss, fluid imbalance, and immunodeficiency. We report the case of a 51-year-old man who developed a persistent high-flow chylothorax after replacement of the descending thoracic aorta for an aneurysm. After a week of complete oral intake cessation and total parenteral nutrition, we started administration of octreotide, a somatostatin analog. It led to rapid cessation of chyle production, and the patient was discharged without further complications and chylothorax relapses.
Full-text · Article · Feb 2007 · Annals of Vascular Surgery