85 research outputs found
Antiplatelet combinations for prevention of atherothrombotic events
Antiplatelet therapy plays a fundamental role in reducing atherothrombotic events by several pathways. The present work reviews available evidence on antiplatelet therapy both for primary prevention and in the presence of established peripheral, cerebral, or cardiac ischemic disease. Due to the importance of adherence to therapy to achieve optimal effects, special attention is given to the use of fixed-dose oral formulations in the clinical subset of patients in whom double antiplatelet therapy has proven indications
Next-generation drug-eluting stents in coronary artery disease: focus on everolimus-eluting stent (Xience V®)
Percutaneous coronary revascularization has been a mainstay in the management of coronary artery disease since its introduction in the late 1970s. Bare-metal stents and, more recently, first-generation drug-eluting stents (DES), such as sirolimus-eluting (Cypher®) and paclitaxel-eluting stents (Taxus®), have further improved results of percutaneous coronary intervention (PCI) by improving early results and reducing the risk of restenosis. There is currently debate on the safety of these first-generation DES, given the potential for late stent thrombosis, especially after discontinuation of dual antiplatelet therapy. There are well known caveats on the performance of their respective metallic stent platforms, delivery, and dilation systems, and polymer coatings. Second-generation DES, such as zotarolimus-eluting (Endeavor®) and everolimus-eluting stents (Xience V®), have recently become available in the USA and/or Europe. The Xience V stent holds the promise of superior anti-restenotic efficacy as well as long-term safety. In addition, this stent is based on the Multi-link platform and delivery system. Recently available data already suggest the superiority of the Xience V stent in comparison to the Taxus stent in terms of prevention of restenosis, without significant untoward events. Nonetheless, the number of patients studied and the follow-up duration are still too limited to enable definitive conclusions. Only indirect meta-analyses can be used to date to compare the Xience V with the Cypher. This systematic review tries to provide a concise and critical appraisal of the data in support of the Xience V everolimus-eluting stent
Mitochondrial DNA methylation is associated with Mediterranean diet adherence in a population of older adults with overweight and obesity.
AbstractIntroductionAdherence to the Mediterranean dietary pattern (MeDiet) and adiposity, respectively, decreases and increases the risk of multiple common age-related diseases through several mechanisms including inflammation, reactive oxygen species (ROS) production in the mitochondria, and DNA methylation. For example, adverse changes in platelets from obese and overweight adults include hyperaggregability and increased ROS. Since platelets are anuclear, their prothrombotic function is fully orchestrated by the mitochondria and the only DNA present is the mitochondrial DNA (mtDNA). In this study, we tested the hypothesis that MeDiet influences patterns of mtDNA methylation in platelets from older adults with greater adiposity.Material and methodsWe selected 134 participants with overweight or obesity (mean BMI = 35.5 ± 5.1 and age = 62 ± 10 years) from the "Susceptibility to particle health effects, miRNA and exosomes"(SPEHRE) Study. Dietary intake was assessed using a food frequency questionnaire and MeDiet adherence was calculated using the MeDiet Score described by Martínez-González et al.(2012). MtDNA was extracted from platelets, linearized, bisulfite converted and DNA methylation was quantified by pyrosequencing at 13 CpG in seven genes that encode for tRNAs (MT-TF and MT-TL1), regulatory regions (D-Loop and MT-OLR), and subunits of the electron-transport-chain (MT-CO1, MT-CO2, and MT-CO3).ResultsIn these participants, MeDiet score ranged from 3 to 12 (mean = 6.5), with higher scores reflecting greater MeDiet adherence. Regression analysis showed that higher MeDiet score was associated with lower D-loop (β = -0.031, P = 0.019) and higher MT-CO2 CpG1 (β = 0.040, P = 0.023) methylation. No associations were found between MeDiet Score and methylation level at MT-CO1(2 CpGs), MT-CO2(CpG2), MT-CO3(2 CpGs), MT-TL1(2 CpGs), MT-TF(CpG1), MT-OLR(3 CpGs).In addition, there was no association between mtDNA methylation and BMI.DiscussionThe D-loop is critical for mitochondrial function since it initiates mtDNA replication and transcription. Increased D-loop methylation has been associated with reduced mitochondrial functionality, and insulin resistance. Our results suggest that higher adherence to MeDiet lowers D-loop methylation which may protect against obesity-related comorbidities (e.g. insulin resistance).Higher MeDiet scores are associated with MT-CO2 CpG1 hypermethylation. MT-CO2 encodes for a subunit of the Cytochrome-C-oxidase, a highly regulated enzyme involved in the oxidative metabolism. MT-CO2 demethylation, induced by Valproic-Acid administration, has been reported to be associated with increased ROS production. Our results suggest a possible role of MeDiet in mitochondrial ROS regulation via methylation of MT-CO2.For the first time, we observed associations between MeDiet adherence and mtDNA methylation. Validation of these findings in independent cohorts is required
Acute coronary syndromes in human immunodeficiency virus patients: a meta-analysis investigating adverse event rates and the role of antiretroviral therapy
Aims Highly active antiretroviral therapy (HAART) dramatically reduces human immunodeficiency virus (HIV)-associated morbidity and mortality, but adverse effects of HAART are becoming an increasing challenge, especially in the setting of acute coronary syndromes (ACS). We thus performed a comprehensive review of studies focusing on ACS in HIV patients. Methods and results MEDLINE/PubMed was systematically screened for studies reporting on ACS in HIV patients. Baseline, treatment, and outcome data were appraised and pooled with random-effect methods computing summary estimates [95% confidence intervals (CIs)]. A total of 11 studies including 2442 patients were identified, with a notably low prevalence of diabetes [10.86 (4.11, 17.60); 95% CI]. Rates of in-hospital death were 8.00% (2.8, 12.5; 95% CI), ascribable to cardiovascular events for 7.90% (2.43, 13.37; 95% CI), with 2.31% (0.60, 4.01; 95% CI) developing cardiogenic shock. At a median follow-up of 25.50 months (11.25, 42; 95% CI), no deaths were recorded, with an incidence of 9.42% of acute myocardial infarction (2.68, 16.17; 95% CI) and of 20.18% (9.84, 30.51; 95% CI) of percutaneous coronary revascularization. Moreover, pooled analysis of the studies reporting incidence of acute myocardial infarction in patients exposed to protease inhibitors showed an overall significant risk of 2.68 (odds ratio 1.89, 3.89; 95% CI). Conclusion Human immunodeficiency virus patients admitted for ACS face a substantial short-term risk of death and a significant long-term risk of coronary revascularization and myocardial infarction, especially if receiving protease inhibitors
An EBC/Plasma miRNA Signature Discriminates Lung Adenocarcinomas From Pleural Mesothelioma and Healthy Controls
Background: Despite significant improvement in screening programs for cancers of the respiratory district, especially in at-risk subjects, early disease detection is still a major issue. In this scenario, new molecular and non-invasive biomarkers are needed to improve early disease diagnosis.
Methods: We profiled the miRNome in exhaled breath condensate (EBC) and plasma samples from fourteen patients affected by lung AdCa, nine healthy subjects. miRNA signatures were then analyzed in another neoplasia of the respiratory district, i.e. pleural mesothelioma (n = 23) and subjects previously exposed to asbestos were used as controls for this cohort (n = 19). Selected miRNAs were analyzed in purified pulmonary neoplastic or normal epithelial and stromal cell subpopulation from AdCa patients. Finally, the plasmatic miRNA signature was analyzed in a publicly available cohort of NSCLC patients for data validation and in silico analysis was performed with predicted miRNA targets using the multiMiR tool and STRING database.
Results: miR-597-5p and miR-1260a are significantly over-expressed in EBC from lung AdCa and are associated with AdCa. Similarly, miR-1260a is also up-regulated in the plasma of AdCa patients together with miR-518f-3p and correlates with presence of lung cancer, whereas let-7f-5p is under-expressed. Analysis of these circulating miRNAs in pleural mesothelioma cases confirmed that up-regulation of miR-518f-3p, -597-5p and -1260a, is specific for lung AdCa. Lastly, quantification of the miRNAs in laser-assisted microdissected lung tissues revealed that miR-518f-3p, 597-5p and miR-1260a are predominantly expressed in tumor epithelial cells. Validation analysis confirmed miR-518f-3p as a possible circulating biomarker of NSCLC. In silico analysis of the potentially modulated biological processes by these three miRNAs, shows that tumor bioenergetics are the most affected pathways.
Conclusions: Overall, our data suggest a 3-miRNAs signature as a non-invasive and accurate biomarker of lung AdCa. This approach could supplement the current screening approaches for early lung cancer diagnosis
Identification of a small molecule that compromises the structural integrity of viroplasms and rotavirus double-layered particles
Despite the availability of two attenuated vaccines, rotavirus (RV) gastroenteritis remains an important cause of mortality among children in developing countries, causing about 215,000 infant deaths annually. Currently, there are no specific antiviral therapies available. RV is a nonenveloped virus with a segmented double-stranded RNA genome. Viral genome replication and assembly of transcriptionally active double-layered particles (DLPs) take place in cytoplasmic viral structures called viroplasms. In this study, we describe strong impairment of the early stages of RV replication induced by a small molecule known as an RNA polymerase III inhibitor, ML-60218 (ML). This compound was found to disrupt already assembled viroplasms and to hamper the formation of new ones without the need for de novo transcription of cellular RNAs. This phenotype was correlated with a reduction in accumulated viral proteins and newly made viral genome segments, disappearance of the hyperphosphorylated isoforms of the viroplasm-resident protein NSP5, and inhibition of infectious progeny virus production. In in vitro transcription assays with purified DLPs, ML showed dose-dependent inhibitory activity, indicating the viral nature of its target. ML was found to interfere with the formation of higher-order structures of VP6, the protein forming the DLP outer layer, without compromising its ability to trimerize. Electron microscopy of ML-treated DLPs showed dose-dependent structural damage. Our data suggest that interactions between VP6 trimers are essential, not only for DLP stability, but also for the structural integrity of viroplasms in infected cells
Preliminary characterization of (nucleoside-2′-O-)-methyltransferase crystals from Meaban and Yokose flaviviruses. Corrigendum
A corrigendum to the paper by Mastrangelo et al. (2006), Acta Cryst. F62, 768–770
Investigation on MMACHC-R161Q pathological mutant from cblC disease
The cblC disease is a rare inborn disorder of the vitamin B12 (cobalamin, Cbl) metabolism characterized by combined methylmalonic aciduria and homocystinuria. The clinical consequences are devastating and, even when early treated with current therapies, the affected children manifest symptoms involving vision, growth, and learning. The molecular genetic cause of the disease was found in the mutations of the gene coding for MMACHC, a 282 amino acid protein that transports and processes the various forms of Cbl.
Here we present the biophysical characterization of wild type MMACHC and a variant, p.R161Q, resulting from the most common missense pathological mutation found in cblC patients.
By using a biophysical approach we investigated the stability of the two proteins and their ability to bind and transform the vitamin B12, and to assemble in a dimeric structure. Moreover, interesting indications about the behaviour of the proteins resulted from the Molecular Dynamics (MD) simulations.
Overall, our results reveal how a biophysical approach based on the complementarity of computational and experimental methods can offer new insights in the study of the specific effects of the pathological cblC mutation and help prospecting new routes for the cblC treatment
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