Search

Diffuse optical tomography (DOT) is an emerging imaging technique which uses light for diagnostic purposes in a non‐invasive and non‐ionizing way. In this paper, we focus on DOT application to female breast screening, where the surface of the breast is illuminated by light sources and the outgoing light is collected on the surface. The comparison of measured light data with the equivalent field obtained from a relevant mathematical model yields the DOT inverse problem whose solution provides an estimate of the optical coefficients of the tissue. These latter, in turn, can be related to clinical markers for cancer detection. The goal of this work is to propose a mathematical and computational approach tailored to the concept of a DOT imaging device able to perform fast and accurate screenings at an affordable cost. Namely, we address two original points about the crucial issue of the solution of the severely ill‐conditioned DOT inverse problem: (a) a computational approach based on Green's functions which do not require the exact knowledge of the tissue geometry, proposed here in the declination of the Method of Fundamental Solutions, which allows to enforce correct boundary conditions; (b) the elastic net regularization technique that shares the desirable properties of both the ℓ2‐ and ℓ1‐norm penalization approaches and opens the possibility for sparsity recognition in the optical coefficients field and refinement procedures. [ABSTRACT FROM AUTHOR]

Intracranial vascular malformations manifest on a continuum ranging from predominantly arterial to predominantly venous in pathology. Cerebral cavernous malformations (CCMs) are capillary malformations that exist at the midpoint of this continuum. The axon guidance factor Ephrin B2 and its receptor EphB4 are critical regulators of vasculogenesis in the developing central nervous system. Ephrin B2/EphB4 dysregulation has been implicated in the pathogenesis of arterial-derived arteriovenous malformations and vein-based vein of Galen malformations. Increasing evidence supports the hypothesis that aberrant Ephrin B2/EphB4 signaling may contribute to developing vascular malformations, but their role in CCMs remains largely uncharacterized. Evidence of Ephrin dysregulation in CCMs would be important to establish a common link in the pathogenic spectrum of EphrinB2/Ephb4 dysregulation. By studying patient-derived primary CCM endothelial cells (CCMECs), we established that CCMECs are functionally distinct from healthy endothelial cell controls; CCMECs demonstrated altered patterns of migration, motility, and impaired tube formation. In addition to the altered phenotype, the CCMECs also displayed an increased ratio of EphrinB2/EphB4 compared to the healthy endothelial control cells. Furthermore, whole exome sequencing identified mutations in both EphrinB2 and EphB4 in the CCMECs. These findings identify functional alterations in the EphrinB2/EphB4 ratio as a feature linking pathophysiology across the spectrum of arterial, capillary, and venous structural malformations in the central nervous system while revealing a putative therapeutic target. [ABSTRACT FROM AUTHOR]

Background: Rheumatic heart valve disease (RHVD) is a leading cause of cardiovascular death in low- and middle-income countries and affects predominantly women. The underlying mechanisms of chronic valvular damage remain unexplored and regulators of sex predisposition are unknown.Methods: Proteomics analysis of human heart valves (nondiseased aortic valves, nondiseased mitral valves [NDMVs], valves from patients with rheumatic aortic valve disease, and valves from patients with rheumatic mitral valve disease; n=30) followed by system biology analysis identified ProTα (prothymosin alpha) as a protein associated with RHVD. Histology, multiparameter flow cytometry, and enzyme-linked immunosorbent assay confirmed the expression of ProTα. In vitro experiments using peripheral mononuclear cells and valvular interstitial cells were performed using multiparameter flow cytometry and quantitative polymerase chain reaction. In silico analysis of the RHVD and Streptococcuspyogenes proteomes were used to identify mimic epitopes.Results: A comparison of NDMV and nondiseased aortic valve proteomes established the baseline differences between nondiseased aortic and mitral valves. Thirteen unique proteins were enriched in NDMVs. Comparison of NDMVs versus valves from patients with rheumatic mitral valve disease and nondiseased aortic valves versus valves from patients with rheumatic aortic valve disease identified 213 proteins enriched in rheumatic valves. The expression of the 13 NDMV-enriched proteins was evaluated across the 213 proteins enriched in diseased valves, resulting in the discovery of ProTα common to valves from patients with rheumatic mitral valve disease and valves from patients with rheumatic aortic valve disease. ProTα plasma levels were significantly higher in patients with RHVD than in healthy individuals. Immunoreactive ProTα colocalized with CD8+ T cells in RHVD. Expression of ProTα and estrogen receptor alpha correlated strongly in circulating CD8+ T cells from patients with RHVD. Recombinant ProTα induced expression of the lytic proteins perforin and granzyme B by CD8+ T cells as well as higher estrogen receptor alpha expression. In addition, recombinant ProTα increased human leukocyte antigen class I levels in valvular interstitial cells. Treatment of CD8+ T cells with specific estrogen receptor alpha antagonist reduced the cytotoxic potential promoted by ProTα. In silico analysis of RHVD and Spyogenes proteomes revealed molecular mimicry between human type 1 collagen epitope and bacterial collagen-like protein, which induced CD8+ T-cell activation in vitro.Conclusions: ProTα-dependent CD8+ T-cell cytotoxicity was associated with estrogen receptor alpha activity, implicating ProTα as a potential regulator of sex predisposition in RHVD. ProTα facilitated recognition of type 1 collagen mimic epitopes by CD8+ T cells, suggesting mechanisms provoking autoimmunity. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate criteria driving retreatment with ranibizumab in Italian patients with myopic choroidal neovascularization (mCNV). Methods: OLIMPIC was a 12-month, phase IIIb, open-label study. Patients with active mCNV were treated with ranibizumab 0.5 mg according to the European label. The study assessed local criteria in Italy driving retreatment decisions with ranibizumab; and the efficacy, safety, and tolerability of ranibizumab. Results: The mean (standard deviation [SD]) age of treated patients (N = 200) was 61.8 (12.7) years; range 22–85 years. The multivariate regression model indicated that presence of active leakage (odds ratio [OR] 95% confidence interval [CI]: 11.30 [1.03–124.14]), presence of intraretinal fluid (OR [95%CI]: 28.21 [1.55–513.73]), and an improvement in best-corrected visual acuity (BCVA) from baseline < 10 letters (OR [95%CI]: 17.60 [1.39–222.75]) were the factors with the greatest effect on retreatment with ranibizumab. The mean (SD) BCVA gain from baseline to month 12 was 8.4 (12.8) letters (P < 0.0001). The mean (SD) number of injections was 2.41 (1.53); range 1–9. Ocular and non-ocular adverse events were reported in 41 (20.5%) and 30 (15.0%) patients, respectively. Conclusions: Individualized treatment with ranibizumab was effective in improving BCVA in patients with mCNV over 12 months. Both anatomical and functional variables had significant effects on causing retreatment. There were no new safety findings. Trial registration: www.ClinicalTrials.Gov (NCT No: NCT02034006) [ABSTRACT FROM AUTHOR]

Background: Some developed countries have recently changed their role in the context of international recruitment, becoming donors due to socio-economical and political factors such as recessions. This is also the case in Italy, where there has been a flow of immigrant nurses out of the country that has been documented over the past several years. In a short time, it has become a donor country to other developed European countries, such as the United Kingdom. Aims: To advance knowledge in the context of human rights conflicts and ethical implications of the decision-making process of nurses who migrate between developed countries, such as from Italy to the United Kingdom, during times of recession. Research design: A case study based on the descriptive phenomenological approach was undertaken in 2014. Participants and research context: A total of 26 Italian newly graduated nurses finding a job in the United Kingdom were interviewed via Skype and telephone. Ethical considerations: The Internal Review Board of the University approved the project. Findings: In accordance with the descriptive phenomenological approach undertaken, three main themes emerged: (1) escaping from the feeling of being refused/rejected in order to be desired, (2) perceiving themselves respected, as a person and as a nurse, in a growth project and (3) returning if the country changes its strategy regarding nurses. Discussion: Ethical implications in the context of human rights, such as autonomy of the decision, social justice and reciprocal obligation, non-maleficence and double effect, have been discussed. Conclusion: The call for investing in nurses and nurses' care in developed countries facing recession is urgent. Investing in nurses means respecting individuals and citizens who are at risk of developing health problems during the recession. [ABSTRACT FROM AUTHOR]

Objective: To elucidate factors, other than those clinical, precipitating the risk of aspiration in hospitalized patients.Design: The Critical Incident Technique was adopted for this study in 2015.Setting: Three departments located in two academic hospitals in the northeast of Italy, equipped with 800 and 1500 beds, respectively.Participants: A purposeful sample of 12 registered nurses (RN), all of whom (i) had reported one or more episodes of aspiration during the longitudinal survey, (ii) had worked ≥3 years in the department, and (iii) were willing to participate, were included.Main Outcome Measure(s): Antecedent factors involved in episodes of aspiration as experienced by RNs were collected through an open-ended interview, and qualitatively analysed.Results: In addition to clinical factors, other factors interacting with each other may precipitate the risk of aspiration episodes during hospitalization: at the nursing care level (misclassifying patients, transferring tasks to other healthcare professionals and standardizing processes to remove potential threats); at the family level (misclassifying patients, dealing with the cultural relevance of eating) and at the environmental level (positioning the patient, managing time pressures, distracting patient while eating, dealing with food consistency and irritating oral medication).Conclusions: At the hospital level, an adequate nursing workforce and models of care delivery, as well as time for initial and continuing patient and family assessment are required. At the unit level, patient-centred models of care aimed at reducing care standardization are also recommended; in addition, nursing, family and environmental factors should be recorded in the incident reports documenting episodes of aspiration. [ABSTRACT FROM AUTHOR]

Background: The ability to respond to mechanical forces is a basic requirement for maintaining endothelial cell (ECs) homeostasis, which is continuously subjected to low shear stress (LSS) and high shear stress (HSS). In arteries, LSS and HSS have a differential impact on EC autophagy processes. However, it is still unclear whether LSS and HSS differently tune unique autophagic machinery or trigger specific autophagic responses in ECs., Methods: Using fluid flow system to generate forces on EC and multiscale imaging analyses on ApoE -/- mice whole arteries, we studied the cellular and molecular mechanism involved in autophagic response to LSS or HSS on the endothelium., Results: We found that LSS and HSS trigger autophagy activation by mobilizing specific autophagic signaling modules. Indeed, LSS-induced autophagy in endothelium was independent of the class III PI3K (phosphoinositide 3-kinase) VPS34 (vacuolar sorting protein 34) but controlled by the α isoform of class II PI3K (phosphoinositide 3-kinase class II α [PI3KCIIα]). Accordingly, reduced PI3KCIIα expression in ApoE -/- mice (ApoE -/- PI3KCIIα +/- ) led to EC dysfunctions associated with increased plaque deposition in the LSS regions. Mechanistically, we revealed that PI3KCIIα inhibits mTORC1 (mammalian target of rapamycin complex 1) activation and that rapamycin treatment in ApoE -/- PI3KCIIα +/- mice specifically rescue autophagy in arterial LSS regions. Finally, we demonstrated that absence of PI3KCIIα led to decreased endothelial primary cilium biogenesis in response to LSS and that ablation of primary cilium mimics PI3KCIIα-decreased expression in EC dysfunction, suggesting that this organelle could be the mechanosensor linking PI3KCIIα and EC homeostasis., Conclusions: Our data reveal that mechanical forces variability within the arterial system determines EC autophagic response and supports a central role of PI3KCIIα/mTORC1 axis to prevent EC dysfunction in LSS regions., Competing Interests: Disclosures None.

Aims: Calcific aortic valve disease (CAVD) is the most common valve disease, which consists of a chronic interplay of inflammation, fibrosis, and calcification. In this study, sortilin (SORT1) was identified as a novel key player in the pathophysiology of CAVD, and its role in the transformation of valvular interstitial cells (VICs) into pathological phenotypes is explored., Methods and Results: An aortic valve (AV) wire injury (AVWI) mouse model with sortilin deficiency was used to determine the effects of sortilin on AV stenosis, fibrosis, and calcification. In vitro experiments employed human primary VICs cultured in osteogenic conditions for 7, 14, and 21 days; and processed for imaging, proteomics, and transcriptomics including single-cell RNA-sequencing (scRNA-seq). The AVWI mouse model showed reduced AV fibrosis, calcification, and stenosis in sortilin-deficient mice vs. littermate controls. Protein studies identified the transition of human VICs into a myofibroblast-like phenotype mediated by sortilin. Sortilin loss-of-function decreased in vitro VIC calcification. ScRNA-seq identified 12 differentially expressed cell clusters in human VIC samples, where a novel combined inflammatory myofibroblastic-osteogenic VIC (IMO-VIC) phenotype was detected with increased expression of SORT1, COL1A1, WNT5A, IL-6, and serum amyloid A1. VICs sequenced with sortilin deficiency showed decreased IMO-VIC phenotype., Conclusion: Sortilin promotes CAVD by mediating valvular fibrosis and calcification, and a newly identified phenotype (IMO-VIC). This is the first study to examine the role of sortilin in valvular calcification and it may render it a therapeutic target to inhibit IMO-VIC emergence by simultaneously reducing inflammation, fibrosis, and calcification, the three key pathological processes underlying CAVD., Competing Interests: Conflict of interest: E.A. has participated in advisory board for Elastrin Therapeutics; G.T. has received consulting fees from Ionis Pharmaceuticals and has participated in advisory boards for Amgen and Sanofi., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Background: Activated macrophages contribute to the pathogenesis of vascular disease. Vein graft failure is a major clinical problem with limited therapeutic options. PCSK9 (proprotein convertase subtilisin/kexin 9) increases low-density lipoprotein (LDL)-cholesterol levels via LDL receptor (LDLR) degradation. The role of PCSK9 in macrophage activation and vein graft failure is largely unknown, especially through LDLR-independent mechanisms. This study aimed to explore a novel mechanism of macrophage activation and vein graft disease induced by circulating PCSK9 in an LDLR-independent fashion., Methods: We used Ldlr mice to examine the LDLR-independent roles of circulating PCSK9 in experimental vein grafts. Adeno-associated virus (AAV) vector encoding a gain-of-function mutant of PCSK9 (rAAV8/D377Y-mPCSK9) induced hepatic PCSK9 overproduction. To explore novel inflammatory targets of PCSK9, we used systems biology in -/- mice to examine the LDLR-independent roles of circulating PCSK9 in experimental vein grafts. Adeno-associated virus (AAV) vector encoding a gain-of-function mutant of PCSK9 (rAAV8/D377Y-mPCSK9) induced hepatic PCSK9 overproduction. To explore novel inflammatory targets of PCSK9, we used systems biology in Ldlr -/- mouse macrophages., Results: In Ldlr mice, AAV-PCSK9 increased circulating PCSK9, but did not change serum cholesterol and triglyceride levels. AAV-PCSK9 promoted vein graft lesion development when compared with control AAV. In vivo molecular imaging revealed that AAV-PCSK9 increased macrophage accumulation and matrix metalloproteinase activity associated with decreased fibrillar collagen, a molecular determinant of atherosclerotic plaque stability. AAV-PCSK9 induced mRNA expression of the pro-inflammatory mediators IL-1β (interleukin-1 beta), TNFα (tumor necrosis factor alpha), and MCP-1 (monocyte chemoattractant protein-1) in peritoneal macrophages underpinned by an in vitro analysis of -/- mouse macrophages stimulated with endotoxin-free recombinant PCSK9. A combination of unbiased global transcriptomics and new network-based hyperedge entanglement prediction analysis identified the NF-κB (nuclear factor-kappa B) signaling molecules, lectin-like oxidized LOX-1 (LDL receptor-1), and SDC4 (syndecan-4) as potential PCSK9 targets mediating pro-inflammatory responses in macrophages.Ldlr -/- mouse macrophages stimulated with endotoxin-free recombinant PCSK9. A combination of unbiased global transcriptomics and new network-based hyperedge entanglement prediction analysis identified the NF-κB (nuclear factor-kappa B) signaling molecules, lectin-like oxidized LOX-1 (LDL receptor-1), and SDC4 (syndecan-4) as potential PCSK9 targets mediating pro-inflammatory responses in macrophages., Conclusions: Circulating PCSK9 induces macrophage activation and vein graft lesion development via LDLR-independent mechanisms. PCSK9 may be a potential target for pharmacologic treatment for this unmet medical need.

Background: Following myocardial infarction, mitral regurgitation (MR) is a common complication. Previous animal studies demonstrated the association of endothelial-to-mesenchymal transition (EndMT) with mitral valve (MV) remodeling. Nevertheless, little is known about how MV tissue responds to ischemic heart changes in humans. Methods: MVs were obtained by the Cardiothoracic Surgical Trials Network from 17 patients with ischemic mitral regurgitation (IMR). Echo-doppler imaging assessed MV function at time of resection. Cryosections of MVs were analyzed using a multi-faceted histology and immunofluorescence examination of cell populations. MVs were further analyzed using unbiased label-free proteomics. Echo-Doppler imaging, histo-cytometry measures and proteomic analysis were then integrated. Results: MVs from patients with greater MR exhibited proteomic changes associated with proteolysis-, inflammatory- and oxidative stress-related processes compared to MVs with less MR. Cryosections of MVs from patients with IMR displayed activated valvular interstitial cells (aVICs) and double positive CD31+ αSMA+ cells, a hallmark of EndMT. Univariable and multivariable association with echocardiography measures revealed a positive correlation of MR severity with both cellular and geometric changes (e.g., aVICs, EndMT, leaflet thickness, leaflet tenting). Finally, proteomic changes associated with EndMT showed gene-ontology enrichment in vesicle-, inflammatory- and oxidative stress-related processes. This discovery approach indicated new candidate proteins associated with EndMT regulation in IMR. Conclusion: We describe an atypical cellular composition and distinctive proteome of human MVs from patients with IMR, which highlighted new candidate proteins implicated in EndMT-related processes, associated with maladaptive MV fibrotic remodeling., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Lupieri, Nagata, Passos, Beker-Greene, Kirkwood, Wylie-Sears, Alvandi, Higashi, Hung, Singh, Bischoff, Levine and Aikawa.)

Aim: To evaluate the role of vitronectin-enriched protein corona on systemic delivery of siRNA-encapsulated cationic lipid nanoparticles (LNPs) to αvβ3 integrin expressing solid tumors. Materials & methods: 1,2-Dioleoyl-3-trimethylammonium-propane LNPs were formulated, protein corona formed in nude mice serum and its impact on drug delivery were analyzed. Results: 1,2-Dioleoyl-3-trimethylammonium-propane-containing LNP led to enhanced recruitment of vitronectin and showed preferential transfection to αvβ3-expressed cells relative to controls. Upon systemic administration in mice, the LNPs accumulated in the αvβ3-expressing endothelial lining of the tumor blood vessels before reaching tumor cells. Conclusion: These results present an optimized LNP that selectively recruits endogenous proteins in situ to its corona which may lead to enhanced delivery and transfection in tissues of interest.

The transition of healthy arteries and cardiac valves into dense, cell-rich, calcified, and fibrotic tissues is driven by a complex interplay of both cellular and molecular mechanisms. Specific cell types in these cardiovascular tissues become activated following the exposure to systemic stimuli including circulating lipoproteins or inflammatory mediators. This activation induces multiple cascades of events where changes in cell phenotypes and activation of certain receptors may trigger multiple pathways and specific alterations to the transcriptome. Modifications to the transcriptome and proteome can give rise to pathological cell phenotypes and trigger mechanisms that exacerbate inflammation, proliferation, calcification, and recruitment of resident or distant cells. Accumulating evidence suggests that each cell type involved in vascular and valvular diseases is heterogeneous. Single-cell RNA sequencing is a transforming medical research tool that enables the profiling of the unique fingerprints at single-cell levels. Its applications have allowed the construction of cell atlases including the mammalian heart and tissue vasculature and the discovery of new cell types implicated in cardiovascular disease. Recent advances in single-cell RNA sequencing have facilitated the identification of novel resident cell populations that become activated during disease and has allowed tracing the transition of healthy cells into pathological phenotypes. Furthermore, single-cell RNA sequencing has permitted the characterization of heterogeneous cell subpopulations with unique genetic profiles in healthy and pathological cardiovascular tissues. In this review, we highlight the latest groundbreaking research that has improved our understanding of the pathological mechanisms of atherosclerosis and future directions for calcific aortic valve disease.

Rationale: Tamoxifen prevents the recurrence of breast cancer and is also beneficial against bone demineralization and arterial diseases. It acts as an ER (estrogen receptor) α antagonist in ER-positive breast cancers, whereas it mimics the protective action of 17β-estradiol in other tissues such as arteries. However, the mechanisms of these tissue-specific actions remain unclear., Objective: Here, we tested whether tamoxifen is able to accelerate endothelial healing and analyzed the underlying mechanisms., Methods and Results: Using 3 complementary mouse models of carotid artery injury, we demonstrated that both tamoxifen and estradiol accelerated endothelial healing, but only tamoxifen required the presence of the underlying medial smooth muscle cells. Chronic treatment with 17β-estradiol and tamoxifen elicited differential gene expression profiles in the carotid artery. The use of transgenic mouse models targeting either whole ERα in a cell-specific manner or ERα subfunctions (membrane/extranuclear versus genomic/transcriptional) demonstrated that 17β-estradiol-induced acceleration of endothelial healing is mediated by membrane ERα in endothelial cells, while the effect of tamoxifen is mediated by the nuclear actions of ERα in smooth muscle cells., Conclusions: Whereas tamoxifen acts as an antiestrogen and ERα antagonist in breast cancer but also on the membrane ERα of endothelial cells, it accelerates endothelial healing through activation of nuclear ERα in smooth muscle cells, inviting to revisit the mechanisms of action of selective modulation of ERα.

Despite the focus placed on cardiovascular research, the prevalence of vascular and valvular calcification is increasing and remains a leading contributor of cardiovascular morbidity and mortality. Accumulating studies provide evidence that cardiovascular calcification is an inflammatory disease in which innate immune signaling becomes sustained and/or excessive, shaping a deleterious adaptive response. The triggering immune factors and subsequent inflammatory events surrounding cardiovascular calcification remain poorly understood, despite sustained significant research interest and support in the field. Most studies on cardiovascular calcification focus on innate cells, particularly macrophages' ability to release pro-osteogenic cytokines and calcification-prone extracellular vesicles and apoptotic bodies. Even though substantial evidence demonstrates that macrophages are key components in triggering cardiovascular calcification, the crosstalk between innate and adaptive immune cell components has not been adequately addressed. The only therapeutic options currently used are invasive procedures by surgery or transcatheter intervention. However, no approved drug has shown prophylactic or therapeutic effectiveness. Conventional diagnostic imaging is currently the best method for detecting, measuring, and assisting in the treatment of calcification. However, these common imaging modalities are unable to detect early subclinical stages of disease at the level of microcalcifications; therefore, the vast majority of patients are diagnosed when macrocalcifications are already established. In this review, we unravel the current knowledge of how innate and adaptive immunity regulate cardiovascular calcification; and put forward differences and similarities between vascular and valvular disease. Additionally, we highlight potential immunomodulatory drugs with the potential to target calcification and propose avenues in need of further translational inquiry., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Anthracyclines such as doxorubicin, daunorubicin, epirubicin, mitoxantrone and idarubicin, are powerful chemotherapeutic drugs used both in children and adult populations. Their properties made them particularly suitable for a large variety of neoplasms including breast adenocarcinoma, small cell lung cancer and acute leukemia. Early and late anthracycline-induced cardiotoxicity is a well-known phenomenon, and the incidence of heart failure in patients receiving doxorubicin is 2.2%, with a mortality rate over 60% at 2 years. Prognosis can be improved by prevention, early detection and treatment. A specific treatment for anthracycline-induced cardiotoxicity is not yet available, but non-pharmacological measures such as exercise, lifestyle changes and control of risk factors have shown a cardioprotective effect. Exercise training represents a viable non-pharmacological treatment as it increases cardiovascular reserve and endothelial function, regulates proapoptotic signaling, protects against reactive oxygen species (ROS), and decreases autophagy/lysosomal signaling. However, no current guidelines are available for prevention management in cancer patients. Pharmacological measures both for prevention and treatment are those used for heart failure (β-blockers, angiotensin-receptor blockers, angiotensin-converting enzyme inhibitors, statins, dexrazoxane and aldosteron antagonists). In this chapter, we will discuss how the evaluation, monitoring and prevention of chemotherapy-related cardiomyopathy is correlated with physical exercise.