Folate-based single cell screening using surface enhanced Raman microimaging

Recent progress in nanotechnology and its application to biomedical settings have generated great advantages in dealing with early cancer diagnosis. The identification of the specific properties of cancer cells, such as the expression of particular plasma membrane molecular receptors, has become crucial in revealing the presence and in assessing the stage of development of the disease. Here we report a single cell screening approach based on Surface Enhanced Raman Scattering (SERS) microimaging. We fabricated a SERS-labelled nanovector based on the biofunctionalization of gold nanoparticles with folic acid. After treating the cells with the nanovector, we were able to distinguish three different cell populations from different cell lines (cancer HeLa and PC-3, and normal HaCaT lines), suitably chosen for their different expressions of folate binding proteins. The nanovector, indeed, binds much more efficiently on cancer cell lines than on normal ones, resulting in a higher SERS signal measured on cancer cells. These results pave the way for applications in single cell diagnostics and, potentially, in theranostic

Large Deviations Principle for the Inviscid Limit of Fluid Dynamic Systems in 2D Bounded Domains

Using a weak convergence approach, we establish a Large Deviation Principle (LDP) for the solutions of fluid dynamic systems in two-dimensional bounded domains subjected to no-slip boundary conditions and perturbed by additive noise. Our analysis considers the convergence of both viscosity and noise intensity to zero. Specifically, we focus on three important scenarios: Navier-Stokes equations in a Kato-type regime, Navier-Stokes equations for fluids with circularly symmetric flows and Second-Grade Fluid equations. In all three cases, we demonstrate the validity of the LDP, taking into account the critical topology $C([0,T];L^2).

Cardiac and Vascular Remodeling After 6 Months of Therapy With Sacubitril/Valsartan: Mechanistic Insights From Advanced Echocardiographic Analysis

14Background: Effects of Sacubitril/Valsartan (S/V) on left ventricular (LV) mechanics and ventricular-arterial coupling in patients with heart failure with reduced ejection fraction (HFrEF) are not completely understood. The aim of this study was to evaluate both cardiac and vascular remodeling in a group of HFrEF patients undergoing S/V therapy. Methods: Fifty HFrEF patients eligible to start a therapy with S/V were enrolled. Echocardiographic evaluation was performed at baseline and after 6 months of followup (FU). Beside standard evaluation, including global longitudinal strain (GLS), estimated hemodynamic forces (HDFs) and non-invasive pressure-volume curves (PV loop) were assessed using dedicated softwares. HDFs were evaluated over the entire cardiac cycle, in systole and diastole, both in apex to base (A-B) and latero-septal (L-S) directions. The distribution of LV HDFs was evaluated by L-S over A-B HDFs ratio (L-S/A-B HDFs ratio). Parameters derived from estimated PV loop curves were left ventricular end-systolic elastance (Ees), arterial elastance (Ea), and ventricular-arterial coupling (VAC). Results: At 6 months of FU indexed left ventricular end-diastolic and end-systolic volumes decreased (EDVi: 101 ± 28mL vs. 86 ± 30mL, p < 0.001; ESVi: 72 ± 23mL vs. 55 ± 24mL, p < 0.001), ejection fraction and GLS significantly improved (EF: 29 ± 6% vs. 37 ± 7%, p < 0.001; GLS: −9 ± 3% vs. −13 ± 4%, p < 0.001). A reduction of Ea (2.11 ± 0.91 mmHg/mL vs. 1.72 ± 0.44 mmHg/mL, p = 0.008) and an improvement of Ees (1.01 ± 0.37 mmHg/mL vs. 1.35 ± 0.6 mmHg/mL, p < 0.001) and VAC (2.3 ± 1.1 vs. 1.5 ± 0.7, p < 0.001) were observed. Re-alignment of HDFs occurred, with a reduction of diastolic L-S/A-B HDFs ratio [23 (20–35)% vs. 20 (11–28) %, p < 0.001]. Conclusion: S/V therapy leads to a complex phenomenon of reverse remodeling involving increased myocardial contractility, HDFs distribution improvement, and afterload reduction.openopenMonosilio, Sara; Filomena, Domenico; Luongo, Federico; Sannino, Michele; Cimino, Sara; Neccia, Matteo; Mariani, Marco Valerio; Birtolo, Lucia Ilaria; Benedetti, Giulia; Tonti, Giovanni; Pedrizzetti, Gianni; Vizza, Carmine Dario; Maestrini, Viviana; Agati, LucianoMonosilio, Sara; Filomena, Domenico; Luongo, Federico; Sannino, Michele; Cimino, Sara; Neccia, Matteo; Mariani, Marco Valerio; Birtolo, Lucia Ilaria; Benedetti, Giulia; Tonti, Giovanni; Pedrizzetti, Gianni; Vizza, Carmine Dario; Maestrini, Viviana; Agati, Lucian

Influence of residual perfusion within the infarct zone on the natural history of left ventricular dysfunction after acute myocardial infarction: A myocardial contrast echocardiographic study

AbstractObjectives. This study used myocardial contrast echocardiography to investigate the extent of residual perfusion within the infarct zone in a select group of patients with recently reperfused myocardial infarction and evaluated its influence on the ultimate infarct size.Background. Limited information is available on the status of myocardial perfusion within postischemic dysfunctional segments at predischarge and on its influence on late regional and global functional recovery.Methods. Twenty patients with acute myocardial infarction were selected for the study. Patients met the following inclusion criteria: 1) single-vessel coronary artery disease; 2) patency of infarct-related artery with persistent postischemic dysfunctional segments at predischarge; 3) stable clinical condition up to 6 months after hospital discharge. All selected patients underwent coronary angiography and myocardial contrast echocardiography before hospital discharge and repeated the echocardiographic examination 6 months later. Patients were grouped according to the pattern of contrast enhancement in predischarge dysfunctional segments.Results. In nine patients (group I), the length of segments showing abnormal contraction coincided with that of the contrast defect segments. In the remaining 11 patients (group II), postischemic dysfunctional segments were partly or completely reperfused. There was no difference between the two groups in asynergic segment length at predischarge (7.3 ± 2.5 vs. 7.2 ± 4.3 cm, p = NS). At follow-up study, asynergic segment length was significantly reduced in group II patients, whereas no changes were observed in group I patients (from 7.2 ± 4.3 to 4.7 ± 3.7 cm, p < 0.005; and from 7.3 ± 2.5 to 7.5 ± 2.9 cm, p = NS, respectively).Conclusions. Among patients with a predischarge patent infarct-related artery, further improvement in regional and global function may be expected during follow-up when residual perfusion in the infarct zone is present

Potential genotoxic effects of low-intensity ultrasound on fibroblasts, evaluated with the cytokinesis-block micronucleus assay

Although medical ultrasound offers compelling opportunities to improve therapy in principle, progress in the field has been limited because of an insufficient understanding of the potential genotoxic and cytotoxic effects of ultrasound on biological systems. This paper is mainly focused on an in vitro study of effects with respect to genotoxicity and viability induced by 1- and 3-MHz medical ultrasound in murine fibroblasts (NIH-3T3) at low-intensity exposure (spatial peak temporal average intensity Ita&lt;0.1W/cm2). The NIH-3T3 cells constitute a well-characterized in vitro cell model in which a genotoxic effect can be predicted by means of a reliable and precise murine cytokinesis-block micronucleus assay. A statistically significant increase in the incidence of micronuclei was observed in sonicated 3T3 cells. In particular, the effects were more evident at 1MHz. Moreover, for each frequency investigated, the occurrence of micronuclei was comparatively more frequent with increasing time of exposure. The possible toxicological implications of the medical ultrasound employed herein deal with the existence of a window of exposure parameters (set well below the intensity of ultrasound cavitation) in which some genotoxic effects may occur without significant cytotoxicity. In this respect, they provide new insight toward the correct risk to benefit balancing of ultrasound-based treatments and for designing innovative therapeutic strategies. © 2014 Elsevier B.V

Dimensional scale effects on surface enhanced Raman scattering efficiency of selfassembled silver nanoparticle clusters

A study of the Surface Enhanced Raman Scattering (SERS) from micrometric metallic nanoparticle aggregates is presented. The sample is obtained from the self-assembly on glass slides of micro-clusters of silver nanoparticles (60 and 100 nm diameter), functionalized with the organic molecule 4-aminothiophenol in water solution. For nanoparticle clusters at the micron scale, a maximum enhancement factor of 109 is estimated from the SERS over the Raman intensity ratio normalized to the single molecule contribution. Atomic force microscopy, correlated to spatially resolved Raman measurements, allows highlighting the connection between morphology and efficiency of the plasmonic system. The correlation between geometric features and SERS response of the metallic structures reveals a linear trend of the cluster maximum scattered intensity as a function of the surface area of the aggregate. On given clusters, the intensity turns out to be also influenced by the number of stacking planes of the aggregate, thus suggesting a plasmonic waveguide effect. The linear dependence results weakened for the largest area clusters, suggesting 30 lm2 as the upper limit for exploiting the coherence over large scale of the plasmonic response