49 research outputs found

    Antimicrobial Peptides Human Beta-Defensin-2 and -3 Protect the Gut During Candida albicans Infections Enhancing the Intestinal Barrier Integrity: In Vitro Study

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    The intestinal mucosa is composed of a monolayer of epithelial cells, which is highly polarized and firmly united to each other thanks to the presence of proteins complexes, called Tight junctions (TJs). Alteration of the mucus layer and TJs causes an increase in intestinal permeability, which can lead to a microbial translocation and systemic disorders. Candida albicans, in addition to its role of commensal, is an opportunistic pathogen responsible for disseminated candidiasis, especially in immunocompromised subjects where the dysbiosis leads to damage of the intestinal mucosal barrier . In this work, we used a line of intestinal epithelial cells able to stably express the genes that encodes human beta defensin-2 (HBD-2) and -3 (HBD-3) to monitor the invasion of C. albicans in vitro. Defensins are a group of antimicrobial peptides (AMPs) found in different living organisms, and are involved in the first line of defense in the innate immune response against pathogens. The results obtained show that the presence of antimicrobial peptides improves the expression of TJs and increases the Trans Epithelial Electrical Resistence value. In addition, the invasive ability of C. albicans in transfected cells is significantly reduced, as well as the expression levels of genes involved in the apoptotic pathway. Through the study of interaction between antimicrobial peptides and microbiota we will be able in the future to better understand the mechanisms by which they exert the host defense function against intestinal pathogens

    Anti-inflammatory effect of simvastatin in an experimental model of spinal cord trauma: involvement of PPAR-α

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    <p>Abstract</p> <p>Background</p> <p>Statins such as simvastatin are inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase used in the prevention of cardiovascular disease. In addition to their cholesterol-lowering activities, statins exert pleiotropic anti-inflammatory effects, which might contribute to their beneficial effects on lipid-unrelated inflammatory diseases. Recently it has been demonstrated that the peroxisome proliferator-activated receptor (PPAR)-α mediates anti-inflammatory effects of simvastatin in vivo models of acute inflammation. Moreover, previous results suggest that PPAR-α plays a role in control of secondary inflammatory process associated with spinal cord injury (SCI).</p> <p>Methods</p> <p>With the aim to characterize the role of PPAR-α in simvastatin activity, we tested the efficacy of simvastatin (10 mg/kg dissolved in saline i.p. 1 h and 6 h after the trauma) in an experimental model of SCI induced in mice by extradural compression of the spinal cord (T6-T7 level) using an aneurysm clip with a closing force of 24 g via a four-level T5-T8 laminectomy, and comparing mice lacking PPAR-α (PPAR-α KO) with wild type (WT) mice. In order to elucidate whether the effects of simvastatin are due to activation of the PPAR-α, we also investigated the effect of a PPAR-α antagonist, GW6471 (1 mg/kg administered i.p. 30 min prior treatment with simvastatin) on the protective effects of on simvastatin.</p> <p>Results</p> <p>Results indicate that simvastatin activity is weakened in PPAR-α KO mice, as compared to WT controls. In particular, simvastatin was less effective in PPAR-α KO, compared to WT mice, as evaluated by inhibition of the degree of spinal cord inflammation, neutrophil infiltration, nitrotyrosine formation, pro-inflammmatory cytokine expression, nuclear factor (NF)-κB activation, inducible nitric-oxide synthase (iNOS) expression, and apoptosis. In addition we demonstrated that GW6471 significantly antagonized the effect of the statin and thus abolished the protective effect.</p> <p>Conclusions</p> <p>This study indicates that PPAR-α can contribute to the anti-inflammatory activity of simvastatin in SCI.</p

    Addition of the Aldose Reductase Inhibitor Benzofuroxane Derivative BF-5m to Prolonged and Moderate Exercise Training Enhanced Protection of the Rat Heart From Type-1 Diabetes

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    Moderate exercise training may not be sufficient to exert beneficial effects on the cardiovascular system because of the long-term multifactorial etiology of diabetic complications. The addition of a proper pharmacological tool to the physical exercise should improve the outcomes of the diabetic damage. Here it is shown that 8 weeks exercise training of type 1 diabetic Sprague-Dawley (SD) rats resulted in a significantly increased heart rate, a 14% increase in the left ventricular ejection fraction (LVEF) increased plasma insulin levels and a 13% decrease in plasma glucose with respect to sedentary animals. The training also resulted in a 22% reduction in cardiac QT interval from a diabetic sedentary value of 185 ± 19 ms. Treatment of trained rats with the new antioxidant and NO-releasing aldose reductase 2 inhibitor 5(6)-(benzo[d]thiazol-2-ylmethoxy) benzofuroxane BF-5m, 20 mg/kg/day, added a further and significant (P &lt; 0.01 vs. sedentary) increase of the LVEF up to 38% at 8 week time point. The long QT interval recorded in trained rats was reduced to further 12% by addition to the training of pharmacological treatment with 20 mg/kg/day BF-5m. At this time, the association of the two treatments improved the expression into the cardiac tissue of sarcoplasmic reticulum Ca2+ ATPase 2 (SERCA2) and manganese superoxide dismutase (MnSOD), and reduced the fibrosis

    Local inhibition of ornithine decarboxylase reduces vascular stenosis in a murine model of carotid injury

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    Objectives: Polyamines are organic polycations playing an essential role in cell proliferation and differentiation, as well as in cell contractility, migration and apoptosis. These processes are known to contribute to restenosis, a pathophysiological process often occurring in patients submitted to revascularization procedures. We aimed to test the effect of alpha-difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase, on vascular cell pathophysiology in vitro and in a rat model of carotid arteriotomy-induced (re) stenosis. Methods: The effect of DFMO on primary rat smooth muscle cells (SMCs) and mouse microvascular bEnd. 3 endothelial cells (ECs) was evaluated through the analysis of DNA synthesis, polyamine concentration, cell viability, cell cycle phase distribution and by RT-PCR targeting cyclins and genes belonging to the polyamine pathway. The effect of DFMO was then evaluated in arteriotomy-injured rat carotids through the analysis of cell proliferation and apoptosis, RT-PCR and immunohistochemical analysis of differential gene expression. Results: DFMO showed a differential effect on SMCs and on ECs, with a marked, sustained anti-proliferative effect of DFMO at 3 and 8 days of treatment on SMCs and a less pronounced, late effect on bEnd. 3 ECs at 8 days of DFMO treatment. DFMO applied perivascularly in pluronic gel at arteriotomy site reduced subsequent cell proliferation and preserved smooth muscle differentiation without affecting the endothelial coverage. Lumen area in DFMO-treated carotids was 49% greater than in control arteries 4 weeks after injury. Conclusions: Our data support the key role of polyamines in restenosis and suggest a novel therapeutic approach for this pathophysiological process. (C) 2013 Elsevier Ireland Ltd. All rights reserved

    COVID-19 and atrial fibrillation: Intercepting lines

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    Almost 20% of COVID-19 patients have a history of atrial fibrillation (AF), but also a new-onset AF represents a frequent complication in COVID-19. Clinical evidence demonstrates that COVID-19, by promoting the evolution of a prothrombotic state, increases the susceptibility to arrhythmic events during the infective stages and presumably during post-recovery. AF itself is the most frequent form of arrhythmia and is associated with substantial morbidity and mortality. One of the molecular factors involved in COVID-19-related AF episodes is the angiotensin-converting enzyme (ACE) 2 availability. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uses ACE2 to enter and infect multiple cells. Atrial ACE2 internalization after binding to SARS-CoV-2 results in a raise of angiotensin (Ang) II, and in a suppression of cardioprotective Ang(1–7) formation, and thereby promoting cardiac hypertrophy, fibrosis and oxidative stress. Furthermore, several pharmacological agents used in COVID-19 patients may have a higher risk of inducing electrophysiological changes and cardiac dysfunction. Azithromycin, lopinavir/ritonavir, ibrutinib, and remdesivir, used in the treatment of COVID-19, may predispose to an increased risk of cardiac arrhythmia. In this review, putative mechanisms involved in COVID-19-related AF episodes and the cardiovascular safety profile of drugs used for the treatment of COVID-19 are summarized

    Film thickness measurements for annular flow in minichannels: Description of the optical technique and experimental results

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    An optical method is developed in order to measure the top and bottom liquid film thicknesses during evaporative annular flow in a horizontal minichannel. This method is based on the detection of liquid-vapor and liquid-solid interfaces. For each flow condition, about 4000 frames (corresponding to an observation time of 2s) are recorded with a high-speed camera. Thus, these frames are processed with an image processing algorithm to obtain the average liquid film measurement. Three different configurations of the camera are tested. The chosen solution ensures a good reliability and accuracy of film measurements. The view section is a 2.95mm glass circular channel and the working fluid is R-245fa. The tests are performed in annular flow, for different vapor qualities. A test facility allows reaching the desired conditions of the flow at the inlet of the test section. The examined saturation temperatures are 40, 60, 80 and 100°C, whereas the mass velocities are 300 and 400kg/m2s. A parameter of eccentricity is introduced to characterize the stratification effect. The influence of the saturation temperature, mass velocity and vapor quality is physically discussed through the Froude and Bond numbers. Finally, by using the top and bottom liquid film measurements, the cross-sectional void fraction is estimated

    Ligasure™ Impact and Ligasure™ Small Jaw in Body Contouring after Massive Weight Loss: A New Perspective

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    Background The most effective dissection technique for elevating flaps in body contouring is still controversial, particularly in high-risk massive weight loss (MWL) patients. LigaSure (Medtronic, Dublin, Ireland) is an energy device commonly used among different surgical specialties to reduce morbidity and improve outcomes. The aim of this study is to investigate the effectiveness of LigaSure Impact and LigaSure Small Jaw in body contouring after MWL compared with conventional technique. Material and methods Patients who underwent abdominoplasty, mastopexy, brachioplasty and thigh lift after MWL at a single center from 1 December 2018 to 1 March 2020 were retrospectively reviewed. In each procedure patients were divided into two groups according to the dissection technique: LigaSure group and monopolar electrosurgery group. Patients characteristics, perioperative details and postoperative complications were evaluated. Results Fourty-five patients underwent abdominoplasty, twenty-six mastopexy, twenty brachioplasty and sixteen medial thigh lift. Using LigaSure, operative time was longer in abdominoplasty and thigh lift, but shorter in mastopexy and brachioplasty. Although not statistically significant, the amount of blood and serum recorded from drains in the first 36 hours was reduced in LigaSure groups. Additional analgesic intake was reduced with LigaSure as well as postoperative subjective pain. In all body contouring procedures statistically significant difference was found in days of hospital stay favoring LigaSure groups. Complications occurred most frequently in control groups compared to LigaSure groups. Conclusion LigaSure Impact and LigaSure Small Jaw may be beneficial in improving outcomes because they might reduce fluids drainage, analgesics intake, hospital stay and postoperative complications

    Myocardial adeno-associated virus serotype 6-βARKct gene therapy improves cardiac function and normalizes the neurohormonal axis in chronic heart failure

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    The upregulation of G protein-coupled receptor kinase 2 in failing myocardium appears to contribute to dysfunctional beta-adrenergic receptor (betaAR) signaling and cardiac function. The peptide betaARKct, which can inhibit the activation of G protein-coupled receptor kinase 2 and improve betaAR signaling, has been shown in transgenic models and short-term gene transfer experiments to rescue heart failure (HF). This study was designed to evaluate long-term betaARKct expression in HF with the use of stable myocardial gene delivery with adeno-associated virus serotype 6 (AAV6)

    Adiponectin elevation by telmisartan ameliorates ischaemic myocardium in Zucker diabetic fatty rats with metabolic syndrome.

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    AIM: This study investigated whether telmisartan, a selective angiotensin type 1 (AT1) receptor antagonist and gamma peroxisome proliferator-activated receptor (PPAR-γ) partial agonist, reduces myocardial ischaemia/reperfusion (I/R) injury in an experimental model of metabolic syndrome. METHODS: Zucker Diabetic Fatty (ZDF) rats were treated for 3 weeks with telmisartan at doses of 2, 7 and 12 mg/kg/day. After treatment, rats were subjected to a 25-min occlusion of the left descending coronary artery followed by 2-h reperfusion (I/R). RESULTS: Telmisartan reduced the extension of the infarct size in a dose-dependent fashion and decreased the levels of plasma troponin I, a specific marker of myocardial damage. Telmisartan also caused a dose-dependent increase in adiponectin both in plasma and cardiac tissue of infarcted ZDF rats. These levels were minimally increased (p < 0.05 vs. vehicle) by telmisartan 7 mg/kg/day and reached the maximum values with the highest dose of 12 mg/kg/day (p < 0.01 vs. vehicle). In contrast, within the infarcted tissue telmisartan decreased the expression of markers of inflammation such as the transcription factor NF-κB, the toll-like receptors TLR2 and TLR4 as well as TNF-α cytokine. Nitrosative stress was maximal in vehicle-treated infarcted hearts as evidenced by increased expression of iNOS, which was almost abolished after treatement with telmisartan. CONCLUSIONS: Treatment of ZDF rats for 3 weeks with telmisartan, a dual angiotensin II receptor antagonist and partial PPAR-γ receptor agonist, resulted in a significant reduction of myocardial damage induced by I/R and was associated with increased adiponectin and a decrease in inflammatory markers
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