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Exposure to passive smoking: a test to predict endothelial dysfunction and atherosclerotic lesions
No full textAcute exposure to environmental tobacco smoke (ETS) is considered to adversely influence atherogenesis. The aim of this article was to assess whether brachial ultrasonography in subjects with endothelial dysfunction after ETS exposure is associated with atherosclerotic lesions. Never smoker healthy volunteers (n = 18) and subjects with a previous myocardial infarction (MI; n = 10) were studied. Healthy volunteers were 12 men (66%) and 6 women (34%) with a mean age of 34 +/- 9 years. Post-MI subjects were men with a mean age of 53.8 +/- 4.8 years. After assessing endothelial function (by brachial ultrasonography) at rest, study subjects underwent brachial ultrasonography twice: in a smoke-free environment and then in the same environment polluted by cigarette combustion (35 ppm carbon monoxide concentration). Carboxyhemoglobin concentration was measured before and after ETS exposure. Baseline brachial-artery diameter, diameter during reactive hyperemia, and diameter after sublingual nitroglycerin (GTN) administration (endothelium-independent vasodilator) were measured at rest and in both smoke-free and smoking environments. Each study subject acted as their own control. No comparison was made between the two groups. A strong correlation between ETS exposure and endothelial dysfunction was observed in both groups. Post-MI subjects also showed endothelium-independent vasodilation worsening, which is usually due to arterial wall alterations. After ETS exposure, mean flow-mediated vasodilation after GTN was significantly (P < .01) reduced only in post-MI subjects (P < .01). Carboxyhemoglobin concentration increased in both groups (P < .01). ETS exposure may be an effective test to identify endothelial dysfunction and arterial wall alterations by using brachial ultrasonograph
Lack of a relationship between circulating gamma-glutamyltransferase levels and carotid intima media thickness in hypertensive and diabetic patients
No full textMarco Nuti, Paolo Spontoni, Chrysanthos Grigoratos, Giulia Dell&#39;Omo, Alberto Balbarini, Roberto PedrinelliDipartimento Cardio Toracico e Vascolare, Universit&agrave; di Pisa, Pisa, ItalyBackground: By increasing the intracellular prooxidant burden, gamma-glutamyltransferase (GGT) may accelerate atherosclerotic vascular disease. That noxious influence may be reflected by circulating enzyme levels, a correlate of cardiovascular risk factors, and a predictor of incident events. To evaluate this hypothesis, we tested the association between circulating GGT and common carotid intima-media thickness (CIMT), a surrogate index of systemic atherosclerotic involvement, in a large and well-characterized group of patients at risk of cardiovascular disease (CVD).Patients: This study analyzed 548 patients with hypertension and/or diabetes and a widely prevalent history of CVD. Subjects with known hepatic disease and abnormal GGT values were excluded.Methods: CIMT (B-mode ultrasonography) values were the mean of four far-wall measurements at both common carotids. Metabolic syndrome (MetS) was diagnosed according to National Cholesterol Education Program-Adult Treatment Panel III criteria. Due to inherent sex-related differences in GGT levels, the data were analyzed separately in males and females in samples dichotomized by the median.Results: The age-adjusted CIMT values did not differ by GGT levels in males or females. In contrast, the carotid wall was consistently thicker in patients with a history of CVD and MetS independent of age and concurrent GGT values. In both sexes, GGT was associated with key components of the MetS such as triglycerides, fasting plasma glucose, and body mass index.Conclusion: The data collected in this mixed group of hypertensive and/or diabetic patients with widely prevalent history of CVD do not support the concept of a direct pathophysiological link between GGT levels within reference limits and atherosclerotic involvement.Keywords: gamma-glutamyltransferase, carotid intima-media thickness, atherosclerosis, metabolic syndrom
Post-traumatic tricuspid valve insufficiency - 2 cases of delayed clinical manifestation
No full textWe present 2 cases of tricuspid insufficiency following blunt chest trauma: 1 was diagnosed 5 months after the trauma and the other; 20 years after the trauma. In both patients, the tricuspid valve was replaced with a porcine bioprosthesis, because valve repair was not considered feasible. These cases emphasize the variability of clinical presentation of post-traumatic tricuspid valve insufficiency and indicate the need for close follow-up of patients after major thoracic trauma
Delivery of natural polyphenols by polymeric nanoparticles improves the resistance of endothelial progenitor cells to oxidative stress
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European Journal of Pharmaceutical Sciences
Volume 50, Issue 3-4, 2013, Pages 393-399
Delivery of natural polyphenols by polymeric nanoparticles improves the resistance of endothelial progenitor cells to oxidative stress (Article)
Felice, F.a ,
Zambito, Y.b,
Belardinelli, E.b,
D'Onofrio, C.c,
Fabiano, A.b,
Balbarini, A.a,
Di Stefano, R.a
a Department of Surgery, Medical, Molecular and Critical Area Pathology, University of Pisa, via Pardisa, 2, 56124 Pisa, Italy
b University of Pisa, Department of Pharmacy, via Bonnano, 33, Pisa, Italy
c University of Pisa, Department of Cultivation and Protection of Ligneous Species G. Scaramuzzi, Via del Borghetto, 80, Pisa, Italy
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Abstract
Purpose Bone marrow-derived endothelial progenitor cells (EPCs) circulate into peripheral blood and significantly contribute to neo-vascularisation and re-endothelialisation as part of the process of vascular repair. Several studies have reported decreased EPC number in the presence of oxidative stress. Aim of this study was to evaluate the validity of mucoadhesive polymeric nanoparticles as a delivery system of natural products able to protect EPCs from oxidative stress. Methods The total polyphenol content and antioxidant capacity of red grape seed extract (GSE) either pre-veraison (p-GSE) or ripe (r-GSE) were measured. Cell viability was evaluated by WST-1 assay. Nanoparticles were prepared by ionotropic crosslinking of two structurally different thiolated quaternary ammonium-chitosan conjugates. A hyaluronic acid solution, containing p-GSE or r-GSE, was added to a stirred solution of each of the two chitosan derivatives to obtain p- or r-GSE loaded nanoparticles (NP) of two types. Results Both GSE types demonstrated strong antioxidant capacity. p-GSE showed a higher content in total polyphenols compared to r-GSE. NP size was in the 310-340 nm range, with 24 h stability, and nearly 100% encapsulation efficiency for both GSE types. NP were internalized by cells to an extent related directly with their surface charge intensity. GSE-NP uptake significantly improved cell viability and resistance to oxidation. Conclusions Nanotechnology has a great potential in nutraceutical delivery. The present results suggest that NP is a highly promising polyphenol carrier system particularly useful to protect EPCs from oxidative stress, thus improving their survival
Guido da Pisa, l’«Epistola a Cangrande» e i primi “accessus” a Dante
No full textIl saggio esamina le introduzioni al poema dantesco leggibili nei proemi dei primi commenti (Iacomo Della Lana, Guido da Pisa, Ottimo ecc.) o presenti isolatamente in alcuni manoscritti, introduzioni che in vario modo coincidono col testo dell’ “Epistola a Cangrande”, di paternità dantesca ancora discussa. In particolare viene svolto un confronto puntuale tra il primo “accessus” di Guido da Pisa, pervenutoci in veste volgare, e l’“Epistola”, che per alcuni studiosi sarebbe posteriore o addirittura attingerebbe al testo guidiano. Il confronto puntuale si estende al proemio latino delle successive redazioni del commento di Guido e al proemio volgare del bolognese Iacomo della Lana (da cui dipendono i vari prologhi dell’Ottimo e del cosiddetto amico dell’Ottimo). In base all’analisi condotta, si conclude che Guido non ha scritto un «Proto-Accessus», confluito poi nell’“Epistola a Cangrande”, e che un proemio latino anonimo, scorporato da essa o altrimenti prodotto, spiega adeguatamente la dinamica tra l’esegeta pisano e il Lana. Guido ha attinto a questo proemio autonomamente, e fors’anche in precedenza, rispetto al Lana, ma quando è stato divulgato il commento laneo il carmelitano pisano ha riscritto su questa base il proprio, salvaguardandone comunque e anzi potenziandone i nuclei esegetici essenziali. In rapporto al contesto generale del volume, il saggio presenta e analizza anche alcune immagini che corredano i commenti di Guido e del Lana e ne esprimono, sulla soglia dell’esegesi, aspetti esegetici fondamentali
Hemolytic anemia 19 years after mitral valve replacement with a porcine bioprosthesis
No full textA 58-year-old man required replacement of a porcine mitral
prosthesis because of severe hemolysis 19 years after implant.
At operation the major pathologic finding was a perforation of one
cusp with calcific deposition limited to the commissures. Clinically
evident hemolytic anemia due to porcine valve dysfunction is
rare particularly occurring very late postoperatively due to cusp
perforation as in the present case
Dynamic foot-exerciser : a validation study and testing in disuse oedema patients
No full textAim. It is well-known that sitting one hour results in swelling and fluid tetention. However sitting for a long-day work or in elderly people with leg disuse, the venous and lymphatic stasis might be important for chronic venous [and lymphatic] disorders (CVD). Physical training programmes developed to prevent CVD are aimed at calf muscles strengthening.
Methods. We studied a patented, dynamic foot-moover or calf muscle pump facilitating device (PPD: VenoGym by Engineer E. Tacconi), designed to encourage the user to do a certain physical and spontaneous activity without any particular effort. A first test showed that a short period of use (half an hour in the morning and half an hour in the afternoon) of PFD induces subjective benefits, confirmed by the sensation of "light legs". Validation was carried out in a griup of 22 healthy people (mean age 52 years, range 27-69) by Photoplethysmography (PPG) and in 4 subjects by Laser Doppler Imaging. Moreover we tested PFD on 12 aged disable people and in 12 patients without mobility problems, based on a special form for the QoL and swelling reduction, color-Duplex and laser-Doppler exams.
Results. PPG analysis showed that the few minutes of exercises with PFD determined a vein emptying of both legs (45%+/-18 M+/-SD right leg and 47+/-18 M+/- SD left leg). Laser-Doppler imaging performed on both feet after 10 minutes of exercise showed a mean reduction of 19% of tissue perfusion. The study carried out on disabled patients, showed an improvement in blood flow and leg swelling reduction in both groups, the most effectiveness in the control group.
Conclusion. PFD device has a proven vasoactive effect both on micro and macrocirculation; the results on disabled confirm the necessity of a valid physical activity
The ejection fraction of the left ventricle in aortic valve diseases, as a prognostic index in view of surgical correction
No full textThrombolytic therapy in peripheral arterial disease.
No full textThe two main causes of peripheral arterial occlusion (PAO) are embolism and thrombosis. Surgical treatment of acute limb ischemia, because of related complications, has a 30-day mortality rate of 15% to 25%. Intra-arterial thrombolysis for lower extremity ischemia is a well-accepted and frequently used technique. It may offer definitive treatment without the need for major surgery in a significant series of patients with acute occlusion of a native leg artery or a by-pass graft. Thrombolysis can offer several potential advantages when compared with surgical therapy. Thrombolytic agents include streptokinase (SK), urokinase (UK), pro-UK and recombinant tissue plasminogen activators (rt-PA-Alteplase and r-PA-Reteplase). All these agents induce a systemic fibrinolytic state. Three prospective randomized trials, ROCHESTER, STILE, and TOPAS, which compared thrombolytic therapy with traditional surgical revascularization for lower limb ischemia, have recently been published. They suggest that thrombolysis, as an initial therapy, reduces the risk of subsequent surgery and improves limb salvage for patients with PAO. Using this approach, the underlying lesions can be identified and treated by transluminal balloon angioplasty or stenting, or by elective surgical revascularization. However, severe bleeding is still a non rare complication of intra-arterial thrombolysis and the risk of intracranial hemorrhage is 1-2%
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