Machine learning-driven multiscale modeling reveals lipid-dependent dynamics of RAS signaling proteins.

RAS is a signaling protein associated with the cell membrane that is mutated in up to 30% of human cancers. RAS signaling has been proposed to be regulated by dynamic heterogeneity of the cell membrane. Investigating such a mechanism requires near-atomistic detail at macroscopic temporal and spatial scales, which is not possible with conventional computational or experimental techniques. We demonstrate here a multiscale simulation infrastructure that uses machine learning to create a scale-bridging ensemble of over 100,000 simulations of active wild-type KRAS on a complex, asymmetric membrane. Initialized and validated with experimental data (including a new structure of active wild-type KRAS), these simulations represent a substantial advance in the ability to characterize RAS-membrane biology. We report distinctive patterns of local lipid composition that correlate with interfacially promiscuous RAS multimerization. These lipid fingerprints are coupled to RAS dynamics, predicted to influence effector binding, and therefore may be a mechanism for regulating cell signaling cascades.

A pitfall in the echographic diagnosis of abdominal aortic aneurysm: when para-aortic lymph nodes are the trick.

The abdominal aortic aneurysm (AAA) is a potentially fatal asymptomatic disease. It progresses silently with clinical complications that, when they occur, constitute a very serious event, frequently resulting in the patient's exitus. As a result, early detection and treatment are critical because the right therapeutic strategy can halt the disease's natural progression. AAA is frequently discovered as an incidental finding during an abdominal ultrasound or a plain X-ray of the abdomen, which is required for other pathologies. The primary diagnostic tool for AAA identification is abdominal B-mode ultrasound. It is cheap, widely available, non-invasive, and has high diagnostic sensitivity. However, this diagnostic tool may fail in rare cases due to misleading anatomical findings. We present an unusual flaw in the echographic AAA evaluation that should be considered during the diagnostic work-up.

Exploring CRD mobility during RAS/RAF engagement at the membrane.

During the activation of mitogen-activated protein kinase (MAPK) signaling, the RAS-binding domain (RBD) and cysteine-rich domain (CRD) of RAF bind to active RAS at the plasma membrane. The orientation of RAS at the membrane may be critical for formation of the RAS-RBDCRD complex and subsequent signaling. To explore how RAS membrane orientation relates to the protein dynamics within the RAS-RBDCRD complex, we perform multiscale coarse-grained and all-atom molecular dynamics (MD) simulations of KRAS4b bound to the RBD and CRD domains of RAF-1, both in solution and anchored to a model plasma membrane. Solution MD simulations describe dynamic KRAS4b-CRD conformations, suggesting that the CRD has sufficient flexibility in this environment to substantially change its binding interface with KRAS4b. In contrast, when the ternary complex is anchored to the membrane, the mobility of the CRD relative to KRAS4b is restricted, resulting in fewer distinct KRAS4b-CRD conformations. These simulations implicate membrane orientations of the ternary complex that are consistent with NMR measurements. While a crystal structure-like conformation is observed in both solution and membrane simulations, a particular intermolecular rearrangement of the ternary complex is observed only when it is anchored to the membrane. This configuration emerges when the CRD hydrophobic loops are inserted into the membrane and helices α3-5 of KRAS4b are solvent exposed. This membrane-specific configuration is stabilized by KRAS4b-CRD contacts that are not observed in the crystal structure. These results suggest modulatory interplay between the CRD and plasma membrane that correlate with RAS/RAF complex structure and dynamics, and potentially influence subsequent steps in the activation of MAPK signaling.

The cardiac paradox of losing weight: a case of gastro-cardiac syndrome.

Thanks to an unusual reversible cause of reflex syncope, a young physician avoided pacemaker implantation. We present the treatment of a bizarre case of gastro-cardiac syndrome, an often-overlooked clinical entity.

The Heart Muscle and Valve Involvement in Marfan Syndrome, Loeys-Dietz Syndromes, and Collagenopathies.

The inherited connective tissue disorders (Marfan syndrome, Loeys-Dietz syndrome [LDS], and Ehlers-Danlos syndrome [EDS]) involve connective tissue of various organ systems. These pathologies share many common features, nonetheless compared to Marfan syndrome, LDS' cardiovascular manifestations tend to be more severe. In contrast, no association is reported between LDS and the presence of ectopia lentis. The EDS are currently classified into thirteen subtypes. There is substantial symptoms overlap between the EDS subtypes, and they are associated with an increased incidence of cardiovascular abnormalities, such as mitral valve prolapse and aortic dissection.

Diagnosis and Management of Cardiovascular Involvement in Friedreich Ataxia.

Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disorder caused by a homozygous GAA triplet repeat expansion in the frataxin gene. Cardiac involvement, usually manifesting as hypertrophic cardiomyopathy, can range from asymptomatic cases to severe cardiomyopathy with progressive deterioration of the left ventricular ejection fraction and chronic heart failure. The management of cardiac involvement is directed to prevent disease progression and cardiovascular complications. However, direct-disease therapies are not currently available for FRDA. The present review aims to describe the current state of knowledge regarding cardiovascular involvement of FRDA, focusing on clinical-instrumental features and management of cardiac manifestation.

Peripheral Artery Disease and Abdominal Aortic Aneurysm: The Forgotten Diseases in COVID-19 Pandemic. Results from an Observational Study on Real-World Management.

Background and Objectives: It is well established that patients with peripheral artery disease (PAD) as well abdominal aortic aneurysm (AAA) have an increased cardiovascular (CV) mortality. Despite this higher risk, PAD and AAA patients are often suboptimality treated. This study assessed the CV profile of PAD and AAA patients, quantifying the survival benefits of target-based risk-factors modification even in light of the COVID-19 pandemic. Materials and Methods: PAD and AAA patients admitted for any reason to the Vascular Unit from January 2019 to February 2020 were retrospectively analyzed. Biochemical and CV profiles as well as ongoing medical therapies were recorded. Benefits of CV risk-factors control were estimated using the SMART-REACH model. A follow-up visit during the year 2020 was scheduled. Results: A total of 669 patients were included. Of these, 190 showed AAA and 479 PAD at any stage. Only 54% of PAD and 41% of AAA patients were on lipid-lowering drugs with non-optimal low-density lipoprotein (LDL) levels for most of them. A better control of all modifiable CV risk-factors based on the current guidelines would offer an absolute risk reduction of the mean 10-year CV risk by 9% in PAD and 14% in AAA. Unfortunately, the follow-up visit was lost because of COVID-19 limitations. Conclusions: Lipid profiles of PAD and AAA patients were far from guideline-based targets, and medical management was suboptimal. In our center, the COVID-19 pandemic impacted on the strict surveillance required in these very high-risk patients. The achievement of guideline-based therapeutic targets would definitively confer additional significant benefits in reducing the CV risk in these patients.

Dynamic Camera Reconfiguration with Reinforcement Learning and Stochastic Methods for Crowd Surveillance.

Crowd surveillance plays a key role to ensure safety and security in public areas. Surveillance systems traditionally rely on fixed camera networks, which suffer from limitations, as coverage of the monitored area, video resolution and analytic performance. On the other hand, a smart camera network provides the ability to reconfigure the sensing infrastructure by incorporating active devices such as pan-tilt-zoom (PTZ) cameras and UAV-based cameras, thus enabling the network to adapt over time to changes in the scene. We propose a new decentralised approach for network reconfiguration, where each camera dynamically adapts its parameters and position to optimise scene coverage. Two policies for decentralised camera reconfiguration are presented: a greedy approach and a reinforcement learning approach. In both cases, cameras are able to locally control the state of their neighbourhood and dynamically adjust their position and PTZ parameters. When crowds are present, the network balances between global coverage of the entire scene and high resolution for the crowded areas. We evaluate our approach in a simulated environment monitored with fixed, PTZ and UAV-based cameras.

[Validation of surgical masks during COVID19 emergency: activities at the University of Napoli Federico II]. / Validazione di maschere chirurgiche nella fase di emergenza COVID19: l'esperienza dell'Università degli Studi di Napoli Federico II.

SUMMARY: During COVID-19 pandemic crisis, Italian Government has approved Law Decree no. 18 of 17 march 2020, in which art. 15 allows enterprises to produce, import and commercialize surgical masks notwithstanding the current rules of product certification. It is just required that the interested enterprises send to the Italian National Institute of Health a selfcertification in which they declare the technical characteristics of the masks and that masks are produced according to the safety requirements. In this context, a technical-scientific unit was established at the University of Napoli Federico II to provide interested enterprises with state-of-the-art consultancy, testing and measurement services, adhering to rigorous scientific protocols. Characterization tests were carried out on 163 surgical masks and/or materials for their construction and they have enabled the identification of pre-screening criteria to simplify the procedure for evaluating surgical masks using methods for assessing the filtration efficiency of particles and aerosols. Based on experimental results, it has been observed that a filtration efficiency for particles with sizes larger that 650 nm (PFE>650) exceeding 35% might guarantees a bacterial filtration efficiency (BFE) higher than 95% while BFE values higher than 98% are obtained when the PFE>650 is larger than 40%. PFE measurement is extremely simpler with respect to BFE, the latter being time-consuming and requiring specific equipment and methods for its realization. Many tested materials have shown the capability to assure high filtration efficiencies but Spundonded-Meltblown-Spunbonded (SMS), that are layers of non-woven fabric with different weights of Meltblown, can simultaneously guarantee high particle filtration efficiencies with pressure drop values (breathability) in the limits to classify the surgical masks as Type II/IIR. In fact, the fabric products analyzed so far have not been able to simultaneously guarantee adequate BFE and breathability values. On the contrary, Spunbonds of adequate weights can virtually verify both requirements and accredit themselves as possible materials for the production of surgical masks, at least of Type I. Further studies are needed to verify the possibility of producing low-cost, reusable surgical masks that could meet the criteria of circular economy.

Radial pseudoaneurysm in elderly: a rare event with undefinied therapeutical approach. A case report and literature review.

Radial artery pseudoaneurysm (RAP) after cardiac catheterization in elderly patients is a rare complication. Clinical manifestations are pain, swelling and haematoma of the harm. The diagnosis is made through doppler ultrasonography, but the best therapeutical option is still matter of debate. Traditionally, surgical treatment has been considered the gold standard but new and less invasive strategies have been recently proposed: ultrasound-guided compression and local injection of thrombin. In this report we describe the unique case of an 84-year-old female patient who developed radial artery pseudoaneurysm after a failed radial artery access for cardiac catheterization. Finally, the pseudoaneurysm was successfully treated by surgical approach as several attempts of local compression failed. We aimed also at reviewing the treatment options of RAP in elderly patients (>75 years old) and the safety/effectiveness reported in literature.

Cognitive Function and Atrial Fibrillation: From the Strength of Relationship to the Dark Side of Prevention. Is There a Contribution from Sinus Rhythm Restoration and Maintenance?

Atrial fibrillation (AF) is the most common chronic cardiac arrhythmia with an increasing prevalence over time mainly because of population aging. It is well established that the presence of AF increases the risk of stroke, heart failure, sudden death, and cardiovascular morbidity. In the last two decades several reports have shown an association between AF and cognitive function, ranging from impairment to dementia. Ischemic stroke linked to AF is a well-known risk factor and predictor of cognitive decline. In this clinical scenario, the risk of stroke might be reduced by oral anticoagulation. However, recent data suggest that AF may be a predictor of cognitive impairment and dementia also in the absence of stroke. Cerebral hypoperfusion, reduced brain volume, microbleeds, white matter hyperintensity, neuroinflammation, and genetic factors have been considered as potential mechanisms involved in the pathogenesis of AF-related cognitive dysfunction. However, a cause-effect relationship remains still controversial. Consequently, no therapeutic strategies are available to prevent AF-related cognitive decline in stroke-free patients. This review will analyze the potential mechanisms leading to cognitive dysfunction in AF patients and examine the available data on the impact of a sinus rhythm restoration and maintenance strategy in reducing the risk of cognitive decline.

The Role of von Willebrand Factor in Vascular Inflammation: From Pathogenesis to Targeted Therapy.

Beyond its role in hemostasis, von Willebrand factor (VWF) is an emerging mediator of vascular inflammation. Recent studies highlight the involvement of VWF and its regulator, ADAMTS13, in mechanisms that underlie vascular inflammation and immunothrombosis, like leukocyte rolling, adhesion, and extravasation; vascular permeability; ischemia/reperfusion injury; complements activation; and NETosis. The VWF/ADAMTS13 axis is implicated in the pathogenesis of atherosclerosis, promoting plaque formation and inflammation through macrophage and neutrophil recruitment in inflamed lesions. Moreover, VWF and ADAMTS13 have been recently proposed as prognostic biomarkers in cardiovascular, metabolic, and inflammatory diseases, such as diabetes, stroke, myocardial infarction, and sepsis. All these features make VWF an attractive therapeutic target in thromboinflammation. Several lines of research have recently investigated "tailor-made" inhibitors of VWF. Results from animal models and clinical studies support the potent anti-inflammatory and antithrombotic effect of VWF antagonism, providing reassuring data on its safety profile. This review describes the role of VWF in vascular inflammation "from bench to bedside" and provides an updated overview of the drugs that can directly interfere with the VWF/ADAMTS13 axis.

Covalent attachment of cyclic TAT peptides to GFP results in protein delivery into live cells with immediate bioavailability.

The delivery of free molecules into the cytoplasm and nucleus by using arginine-rich cell-penetrating peptides (CPPs) has been limited to small cargoes, while large cargoes such as proteins are taken up and trapped in endocytic vesicles. Based on recent work, in which we showed that the transduction efficiency of arginine-rich CPPs can be greatly enhanced by cyclization, the aim was to use cyclic CPPs to transport full-length proteins, in this study green fluorescent protein (GFP), into the cytosol of living cells. Cyclic and linear CPP-GFP conjugates were obtained by using azido-functionalized CPPs and an alkyne-functionalized GFP. Our findings reveal that the cyclic-CPP-GFP conjugates are internalized into live cells with immediate bioavailability in the cytosol and the nucleus, whereas linear CPP analogues do not confer GFP transduction. This technology expands the application of cyclic CPPs to the efficient transport of functional full-length proteins into live cells.

Versatile and Efficient Site-Specific Protein Functionalization by Tubulin Tyrosine Ligase.

A novel chemoenzymatic approach for simple and fast site-specific protein labeling is reported. Recombinant tubulin tyrosine ligase (TTL) was repurposed to attach various unnatural tyrosine derivatives as small bioorthogonal handles to proteins containing a short tubulin-derived recognition sequence (Tub-tag). This novel strategy enables a broad range of high-yielding and fast chemoselective C-terminal protein modifications on isolated proteins or in cell lysates for applications in biochemistry, cell biology, and beyond, as demonstrated by the site-specific labeling of nanobodies, GFP, and ubiquitin.

Live-cell targeting of his-tagged proteins by multivalent N-nitrilotriacetic acid carrier complexes.

Selective and fast labeling of proteins in living cells is a major challenge. Live-cell labeling techniques require high specificity, high labeling density, and cell permeability of the tagging molecule to target the protein of interest. Here we report on the site-specific, rapid, and efficient labeling of endogenous and recombinant histidine-tagged proteins in distinct subcellular compartments using cell-penetrating multivalent chelator carrier complexes. In vivo labeling was followed in real time in living cells, demonstrating a high specificity and high degree of colocalization in the crowded cellular environment.

Inflammation and cardiovascular disease: from pathogenesis to therapeutic target.

Atherosclerosis represents the most common pathological substrate of coronary heart disease (CHD), and the characterization of the disease as a chronic low-grade inflammatory condition is now largely accepted. A number of mediators of inflammation have been widely studied, both as surrogate biomarkers and as causal agents, in the pathophysiological network of atherogenesis and plaque vulnerability. The epidemiological observation that biomarkers of inflammation are associated with clinical cardiovascular risk supports the theory that targeted anti-inflammatory treatment appears to be a promising strategy in reducing residual cardiovascular risk on the background of traditional medical therapy. A large number of randomized controlled trials have shown that drugs commonly used in cardiovascular disease (CVD), such as statins, may be effective in the primary and secondary prevention of cardiovascular events through an anti-inflammatory effect. Moreover, several anti-inflammatory drugs are being tested for their potential to reduce residual cardiovascular risk on the background of validated medical therapy for atherosclerotic disease. In this paper, we review relevant evidence with regard to the relationship between inflammation and CVD, from pathogenesis to therapeutic strategies.

Angiotensin-converting enzyme inhibitors, statins and the polypill in cardiovascular diseases prevention: ignorance is bliss or not?

The polypill strategy, which combines several medicines that simultaneously control different risk factors/diseases in a single pill, is one of the approaches used in cardiovascular therapy. In different guidelines, this one-pill combination therapy is suggested as first-line step in disease management. Because the cardiovascular diseases (CVD) pandemia, prevention is essential. The approaches that could improve adherence are of great importance to achieve health, social and economical benefits. However, direct or indirect experience of adverse drug reaction is often the reason for discontinuation, with serious fatal and non-fatal consequences especially for a polypill. Angiotensin-converting enzyme inhibitors (ACEi) and statins are the most prescribed medications in CVD prevention. It is well known that both drugs may have adverse effects that induce discontinuation. Often, the personal awareness of these effects is a reason for self-discontinuation. In this study an analysis of the ACEi/statin awareness is reported. Is it potentially harmful for polypill?

Analysis of Carbon Nanoparticle Coatings via Wettability.

Wettability, typically estimated through the contact angle, is a fundamental property of surfaces with wide-ranging implications in both daily life and industrial processes. Recent scientific interest has been paid to the surfaces exhibiting extreme wettability: superhydrophobic and superhydrophilic surfaces, characterized by high water repellency and exceptional water wetting, respectively. Both chemical composition and morphology play a role in the determination of the wettability "performance" of a surface. To tune surface-wetting properties, we considered coatings of carbon nanoparticles (CNPs) in this study. They are a new class of nanomaterials synthesized in flames whose chemistry, dimension, and shape depend on combustion conditions. For the first time, we systematically studied the wettability of CNP coatings produced in a controlled rich ethylene/air flame stabilized over a McKenna burner. A selected substrate was intermittently inserted in the flame at 15 mm above the burner to form a thin coating thanks to a thermophoretic-driven deposition mechanism. The chemical-physical quality and the deposed quantity of the CNPs were varied by opportunely combing the substrate flame insertion number (from 1 to 256) and the carbon-to-oxygen ratio, C/O (from 0.67 to 0.87). The wettability of the coatings was evaluated by measuring the contact angle, CA, with the sessile drop method. When the C/O = 0.67, the CNPs were nearly spherical, smaller than 8 nm, and always generated hydrophilic coatings (CA < 35°). At higher C/O ratios, the CNPs reached dimensions of 100 nm, and fractal shape aggregates were formed. In this case, either hydrophilic (CA < 76°) or superhydrophobic (CA ~166°) behavior was observed, depending on the number of carbon nanoparticles deposed, i.e., film thickness. It is known that wettability is susceptible to liquid surface tension, and therefore, tests were conducted with different fluids to establish a correlation between the flame conditions and the nanostructure of the film. This method offers a fast and simple approach to determining mesoscale information for coating roughness and topographical homogeneity/inhomogeneity of their surfaces.

Evolving Concepts of the SCORE System: Subtracting Cholesterol from Risk Estimation: A Way for a Healthy Longevity?

The role of cholesterol, mainly low-density lipoproteins (LDL-C), as a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) is now established and accepted by the international scientific community. Based on this evidence, the European and American guidelines recommend early risk stratification and "rapid" achievement of the suggested target according to the risk estimation to reduce the number of major cardiovascular events. Prolonged exposure over the years to high levels of LDL-C is one of the determining factors in the development and progression of atherosclerotic plaque, on which the action of conventional risk factors (cigarette smoking, excess weight, sedentary lifestyle, arterial hypertension, diabetes mellitus) as well as non-conventional risk factors (gut microbiota, hyperuricemia, inflammation), alone or in combination, favors the destabilization of the atherosclerotic lesion with rupture/fissuration/ulceration and consequent formation of intravascular thrombosis, which leads to the acute clinical manifestations of acute coronary syndromes. In the current clinical practice, there is a growing number of cases that, although extremely common, are emblematic of the concept of long-term exposure to the risk factor (LDL hypercholesterolemia), which, not adequately controlled and in combination with other risk factors, has favored the onset of major cardiovascular events. The triple concept of "go lower, start earlier and keep longer!" should be applied in current clinical practice at any level of prevention. In the present manuscript, we will review the current evidence and documents supporting the causal role of LDL-C in determining ASCVD and whether it is time to remove it from any score.