How solid is solidity? An in-dept study of solidity’s type safety.

Blockchain has evolved a lot in the last years: one of the most important features is the possibility, for mutually untrusted parties, to interact with one another without relying on a third party trusted entity. This interaction is made possible by the so-called smart contracts, passive arbitrary programs executed in a decentralized network and usually manipulating money. One of the main platforms in this sense is Ethereum, and a number of programming languages exist in its ecosystem, all with points of strength and flaws. Of these, the most widely used is for sure Solidity. In spite of its high potential, repeated security concerns have undercut the trust in this way of handling money. Bugs and undesired behaviors are worsened by the impossibility of patching a contract once it is deployed on the blockchain. As a consequence, many analysis tools have been developed by researchers. However, those operating on Solidity lack a real formalization of the core of this language. We aim to fill the gap with Featherweight Solidity (FS). To the best of our knowledge, this is the first calculus including the semantics as well as the type system. Thanks to it, we proved the theorem of Type Safety for Solidity (claimed in the official documentation, although not supported by any public proof). We also formalized, and proved, an extended Type Safety statement addressing groups of transactions. During this process, we found out that Solidity's type system is far from being safe with respect to any type of error: in many occasions, contract interfaces are not consulted at compile-time, and this makes the execution raise an exception and the user waste money. Sometimes, in particular when transferring money from one party to another, exceptions can be avoided by simply looking at, at compile-time, contract interfaces. We also propose an extension of the type system, FS+, that targets this undesired behavior. We prove that Type Safety is maintained, but we formalize additional theorems stating new safety properties, too. In particular, but not only, FS+ statically detects, and consequently rules out, ill-formed money transfers made by means of the Solidity's built-in transfer function. We compared it with Solidity, and showed that including this extension does not change radically the way of writing smart contracts, whereas it makes them much safer.ope

Why patients with familial hypercholesterolemia are at high cardiovascular risk? Beyond LDL-C levels

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Lifestyle interventions and nutraceuticals: Guideline-based approach to cardiovascular disease prevention

Abstract Lowering low-density lipoprotein cholesterol (LDL-C) levels is associated with a well-documented reduction in cardiovascular (CV) disease (CVD) risk. Current guidelines and literature support lifestyle interventions as the primary strategy for reducing CV risk. Association of dietary modifications (such as the Mediterranean diet), physical activity and the cessation of smoking with reduced CV morbidity and mortality has been evidenced. Where lifestyle interventions are not adequate for lowering LDL-C levels and CV risk, pharmacological therapies, most commonly statins, may also be considered. The benefits of lifestyle and pharmacological interventions in the prevention of CVD are widely known, but poor adherence and persistence to these necessitate an approach that aims to improve LDL-C lowering for CVD prevention. Nutraceuticals (targeted functional foods or dietary supplements of plant or microbial origin) are included in EU guidelines as lifestyle interventions and may provide an additional approach to controlling LDL-C levels when a pharmaceutical intervention is not (yet) indicated. However, among different nutraceuticals, the level of clinical evidence supportive of efficacy for lipid lowering needs to be considered. Meta-analyses of randomised clinical trials have demonstrated that some nutraceuticals (e.g. red yeast rice and berberine) and some nutraceutical combinations improve lipid profiles, including lowering of LDL-C, total cholesterol and triglyceride levels. Therefore, nutraceuticals may be considered in specific patient groups where there is appropriate evidence to support the efficacy and safety

regulation of cardiac stem cells by micrornas state of the art

Abstract Stem cells have a therapeutic potential in various medical conditions. In cases without sufficient response to conventional drug treatments, stem cells represent a next generation therapeutic strategy in cardiovascular diseases. Cardiac stem cells (CSCs), among a wide variety of stem cell sources, have been identified as a valid option for stem cell-based therapy in cardiovascular diseases. CSCs mainly act as a cell source to supply the physiological need for cardiovascular cells. However, they have been demonstrated to reproduce the myocardial cells under pathological settings. Despite their roles and functions have somewhat been clarified, molecular pathways underlying the regulatory mechanisms of CSCs are still not fully elucidated. Several studies have recently shown that different microRNAs (miRNAs) play a substantial role in regulating and controlling both the physiological and pathological proliferation and differentiation of stem cells. MiRNAs are small non-coding RNA molecules that regulate gene expression and may undergo aberrant expression levels during pathological conditions. Understanding the way through which miRNAs regulate CSC behavior may open up new horizons in modulating these cells in vitro to devise sophisticated approaches for treating patients with cardiovascular diseases. In this review article, we tried to discuss available evidence about the role of miRNAs in regulating CSCs

Hypercholesterolemia and cardiovascular disease: What to do before initiating pharmacological therapy.

Abstract The availability of efficient lipid-lowering drugs has substantially reduced the incidence and mortality for cardiovascular disease (CVD). Despite that, CVD still represents a major cause of death and disability; efforts are thus required to prevent this disease, since reducing the established CV risk factors may slow or prevent the onset of cardiovascular events. Current guidelines recommend a healthier lifestyle for all CV risk categories, as it may have a beneficial impact on several risk factors; in individuals with a low-to-moderate hypercholesterolemia, which are not eligible for a pharmacological approach and are not far from the cholesterol target recommended for their risk category, functional foods or nutraceuticals may be considered as supplement to reduce their CV risk status. Of note, counseling and lifestyle intervention in people at moderate CV risk represents a major issue for both preventing a further risk increase and reducing the need for drugs. Studies on general populations have clearly indicated that lifestyle interventions translate into a clinical benefit, with reduction of the incidence of myocardial infarction and the risk of developing type 2 diabetes

A systematic review and meta-analysis on the effects of statins on pregnancy outcomes.

Abstract Background and aims Statins are contraindicated in pregnancy, due to their potential teratogenicity. However, data are still inconsistent and some even suggest a potential benefit of statin use against pregnancy complications. We aimed to investigate the effects of statins on pregnancy outcomes, including stillbirth, fetal abortion, and preterm delivery, through a systematic review of the literature and a meta-analysis of the available clinical studies. Methods A literature search was performed through PubMed, Scopus, and Web of Science up to 16 May 2020. Data were extracted from 18 clinical studies (7 cohort studies, 2 clinical trials, 3 case reports, and 6 case series). Random effect meta-analyses were conducted using the restricted maximum likelihood method. The common effect sizes were calculated as odds ratios (ORs) and their 95% confidence interval (CI) for each main outcome. Results Finally, nine studies were included in the meta-analysis. There was no significant association between statin therapy and stillbirth [OR (95% CI) = 1.30 (0.56, 3.02), p=0.54; I2 = 0%]. While statin exposure was significantly associated with increased rates of spontaneous abortion [OR (95% CI) = 1.36 (1.10–1.68), p=0.004, I2 = 0%], it was non-significantly associated with increased rates of induced abortion [OR (95% CI) = 2.08 (0.81, 5.36), p=0.129, I2 = 17.33%] and elective abortion [OR (95% CI) = 1.37 (0.68, 2.76), p=0.378, I2 = 62.46%]. A non-significant numerically reduced rate of preterm delivery was observed in statin users [OR (95% CI) = 0.47 (0.06, 3.70), p=0.47, I2 = 76.35%]. Conclusions Statin therapy seems to be safe as it was not associated with stillbirth or induced and elective abortion rates. Significant increase after statin therapy was, however, observed for spontaneous abortion. These results need to be confirmed and validated in future studies

Association Between Uric Acid, Carotid Intima-Media Thickness, and Cardiovascular Events:Prospective Results From the IMPROVE Study

Background The association between elevated serum uric acid (SUA), cardiovascular disease (CVD) risk, and carotid atherosclerosis has long been explored, and contrasting results have been reported. Therefore, the role of SUA as an independent risk factor for vascular events (VEs) and carotid atherosclerosis deserves further attention. We investigated the relationship between SUA, incident VEs, carotid intima-media thickness (cIMT), and cIMT progression in subjects at moderate-to-high CVD risk. Methods and Results In the IMPROVE (IMT-Progression as Predictors of VEs) study, 3686 participants (median age 64 years; 48% men) with >= 3 vascular risk factors, free from VEs at baseline, were grouped according to SUA quartiles (division points: 244-284-328 mu mol/L in women, 295-336-385 mu mol/L in men). Carotid-IMT and its 15-month progression, along with incident VEs, were recorded. A U-shaped association between SUA and VEs was observed in men, with 2.4-fold (P = 0.004) and 2.5-fold (P = 0.002) increased CVD risk in the first and fourth SUA quartiles as compared with the second. Adjusted hazard ratios (HRs) for cerebro-VEs in men were the highest (first and fourth quartile versus second: HR, 5.3, P = 0.010 and HR, 4.4, P = 0.023, respectively). SUA level was independently associated with cIMT progression in men (beta = 0.068, P = 0.014). No significant association between SUA levels, CVD end points, and cIMT progression were found in women. Conclusions Both low and high SUA levels are associated with an increased risk of VEs in men at moderate-to-high CVD risk but not in women. Only elevated SUA levels predict cIMT progression and at a lesser but not significant extent in women