2,317 research outputs found

    Getting old through the blood. Circulating molecules in aging and senescence of cardiovascular regenerative cells

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    Global aging is a hallmark of our century. The natural multifactorial process resulting in aging involves structural and functional changes, affecting molecules, cells, and tissues. As the western population is getting older, we are witnessing an increase in the burden of cardiovascular events, some of which are known to be directly linked to cellular senescence and dysfunction. In this review, we will focus on the description of a few circulating molecules, which have been correlated to life span, aging, and cardiovascular homeostasis. We will review the current literature concerning the circulating levels and related signaling pathways of selected proteins (insulin-like growth factor 1, growth and differentiation factor-11, and PAI-1) and microRNAs of interest (miR-34a, miR-146a, miR-21), whose bloodstream levels have been associated to aging in different organisms. In particular, we will also discuss their potential role in the biology and senescence of cardiovascular regenerative cell types, such as endothelial progenitor cells, mesenchymal stromal cells, and cardiac progenitor cells

    Analysis of second harmonic generation in photonic-crystal-assisted waveguides

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    We study second harmonic generation in a planar dielectric waveguide having a low-index, polymer core layer, bounded by two multilayer stacks. This geometry allows exceptionally strong confinement of the light at the fundamental wavelength inside the core region with virtually zero net propagation losses for distances that exceed several centimeters, provided material and scattering losses are neglected. A phase-matched configuration of the waveguide is reported in which the pump signal is the lowest-order mode of the waveguide, and the generated second harmonic signal corresponds to the third propagation mode of the waveguide. Using a polymer waveguide core, having chi(2)=100 pm/V, we predict a conversion efficiency of approximately 90% after a propagation distance of 2 mm, using peak pump intensities inside the core of the waveguide of 1.35 GW/cm^2. If the waveguide core contains polymer layers with different glass transition temperatures, the layers can be poled independently to maximize the overlap integral, and similar pump depletions may be achieved over a distance of approximately 500 microns.Comment: 20 pages, 7 figures, 330k

    Interception of virtual throws reveals predictive skills based on the visual processing of throwing kinematics

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    Predicting the outcome of observed actions is fundamental for efficient interpersonal interactions. This is evident in interceptive sports, where predicting the future ball trajectory could make apart success and fail. We quantitatively assessed the predictive abilities of non-trained adults intercepting thrown balls in immersive virtual reality. Participants performed better when they could see the complete throwing action in addition to the ball flight, and they were able to move toward the correct direction when the ball flight was occluded. In both cases, performance varies with the individual motor style of the thrower. These results prove that humans can effectively predict the unfolding of complex full-body actions, with no need to extensively practice them, and that such predictions are exploited online to optimize interactive motor performance. This suggests that humans hold a functional knowledge of how actions recurrent in the human motor repertoire map into the changes brought to the environment

    Atherosclerosis is associated with a higher risk of hepatic steatosis in HIV-infected patients

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    Introduction. Cardiovascular Diseases (CD) have emerged as a leading cause of morbidity and mortality in HIV population. Some studies have reported higher carotid Intima Media Thickness (c-IMT), a measure of subclinical atherosclerosis (AT), in this cohort of patients.Methods. Here, we evaluate the role of Hepatic Steatosis (HS) as likely marker for AT in 128 HIV-infected patients without  hepatitis C infection. c-IMT has been detected non-invasively by carotid ultrasonography to assess the progression of AT. HS has been evaluated using a process based on vibration-controlled transient elastography (Fibroscan) by a novel ultrasonic controlled attenuation parameter (CAP). The cut-off value for defining the presence of significant HS was CAP > 259 dBm-1. Results. AT has been detected in 26 patients (20.3%), whereas steatosis of grade 2 (S2) in 31 (24.2%). The variables statistically related to AT were age, obesity, diabetes, hypertension and S2. In the multivariate analysis, AT was only associated (p < 0.001) with age and S2. The optimal cut-off value indicated by ROC curve for predicting AT was CAP > 250 dB/m-1.Discussion. Our results highlight the presence of AT in HIV-infected persons and its association with fatty liver disease; therefore, HS assessment in HIV population results crucial to predict AT and CD

    Heuristic search for equivalence checking

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    Equivalence checking plays a crucial role in formal verification since it is a natural relation for expressing the matching of a system implementation against its specification. In this paper, we present an efficient procedure, based on heuristic search, for checking well-known bisimulation equivalences for concurrent systems specified through process algebras. The method tries to improve, with respect to other solutions, both the memory occupation and the time required for proving the equivalence of systems. A prototype has been developed to evaluate the approach on several examples of concurrent system specifications

    New architectural design of delivery room reduces morbidity in preterm neonates: a prospective cohort study

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    Background: A multidisciplinary committee composed of a panel of experts, including a member of the American Academy of Pediatrics and American Institute of Architects, has suggested that the delivery room (DR) and the neonatal intensive care units (NICU) room should be directly interconnected. We aimed to investigate the impact of the architectural design of the DR and the NICU on neonatal outcome. Methods: Two cohorts of preterm neonates born at < 32weeks of gestational age, consecutively observed during 2years, were compared prospectively before (Cohort 1: "conventional DR") and after architectural renovation of the DR realized in accordance with specific standards (Cohort 2: "new concept of DR"). In Cohort 1, neonates were initially cared for a conventional resuscitation area, situated in the DR, and then transferred to the NICU, located on a separate floor of the same hospital. In Cohort 2 neonates were assisted at birth directly in the NICU room, which was directly connected to the DR via a pass-through door. The primary outcome of the study was morbidity, defined by the proportion of neonates with at least one complication of prematurity (i.e., late-onset sepsis, patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity and necrotizing enterocolitis). Secondary outcomes were mortality and duration of hospitalization. Statistical analysis was performed using standard methods by SPSS software. Results: We enrolled 106 neonates (56 in Cohort 1 and 50 in Cohort 2). The main clinical and demographic characteristics of the 2cohorts were similar. Moderate hypothermia (body temperature ≤ 35.9° C) was more frequent in Cohort 1 (57%) compared with Cohort 2 (24%, p = 0.001). Morbidity was increased in Cohort 1 (73%) compared with Cohort 2 (44%, p = 0.002). No statistically significant differences in mortality and median duration of hospitalization were observed between the 2 cohorts of the study. Conclusions: If realized according to the proposed architectural standards, renovation of DR and NICU may represent an opportunity to reduce morbidity in preterm neonates

    Is hydrogen electronegativity higher than Pauling's value? New clues from the 13C and 29Si NMR chemical shifts of [CHF3] and [SiHF3] molecules

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    Abstract We previously demonstrated that the δ NMR chemical shift of central NMR active atoms (A), in simple halido [AXn] (A=C, Si, Ge, Sn, Pb, Pt; Xn = combination of n halides, n = 4 or 6) derivatives, could be directly related to X radii overall sum, Σ(r L ). Further correlation have also been observed for tetrahedral [AX4] (A=C, Si; X4 = combination of four halides) compounds where the X Pauling electronegativities sum, Σ ( χ L Pau ) , Σ(χLPau),\Sigma (\chi _L^{{\rm{Pau}}}), exceeds a specific value (≈12.4). In this work, we focused on these latter systems considering the H vs. X substitution. The analysis of the literature reported δ(13C) and δ(29Si) NMR chemical shift for the mono hydrogenated derivatives and in particular for [CHF3] and [SiHF3], characterized by the lowest Σ(r L ) and the highest Σ ( χ L Pau ) , Σ(χLPau),\Sigma (\chi _L^{{\rm{Pau}}}), suggests a revised value for the H electronegativity ranking with respect to Pauling's

    The Benefit of Sleeve Gastrectomy in Obese Adolescents on Nonalcoholic Steatohepatitis and Hepatic Fibrosis

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    Objective To determine whether bariatric surgery is effective for the treatment of nonalcoholic steatohepatitis (NASH) in adolescence, we compared the efficacy of laparoscopic sleeve gastrectomy (LSG) with that of lifestyle intervention (nonsurgical weight loss [NSWL]) for NASH reversal in obese adolescents. Study design Obese (body mass index ≥ 35 kg/m2) adolescents (13-17 years of age) with biopsy-proven NAFLD underwent LSG, lifestyle intervention plus intragastric weight loss devices (IGWLD), or only NSWL. At baseline and 1 year after treatment, patients underwent clinical and psychosocial evaluation, blood tests, liver biopsy, polysomnography, and 24-hour ambulatory blood pressure estimation. Results Twenty patients (21%) underwent LSG, 20 (21%) underwent IGWLD, and 53 (58%) received lifestyle intervention alone (NSWL). One year after treatment, patients who underwent LSG lost 21.5% of their baseline body weight, whereas patients who underwent IGWLD lost 3.4%, and patients who underwent NSWL increase 1.7%. In patients who underwent LSG, NASH reverted completely in all patients and hepatic fibrosis stage 2 disappeared in 18 patients (90%). After IGWLD, NASH reverted in 6 patients (24%) and fibrosis in 7 (37%). Patients who received the NSWL intervention did not improve significantly. Hypertension resolved in all patients who underwent LSG with preoperative hypertension (12/12) versus 50% (4/8) of the patients who underwent IGWLD (P = .02). The cohort-specific changes in impaired glucose metabolism were similar: 100% (9/9) of affected patients who underwent LSG versus 50% (1/2) of patients who underwent IGWLD (P = .02). LSG was also more affective in resolving dyslipidemia (55% [7/12] vs 26% [10/19]; P = .05) and sleep apnea (78% [2/9] vs 30% [11/20]; P = .001). Conclusion LSG was more effective than lifestyle intervention, even when combined with intragastric devices, for reducing NASH and liver fibrosis in obese adolescents after 1 year of treatment

    Giant Malignant Granular Cell Tumor (GCT) of the Posterior Mediastinum

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    The Status of \u3ci\u3ePosidonia oceanica\u3c/i\u3e at Tremiti Islands Marine Protected Area (Adriatic Sea)

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    Simple Summary: The seagrass Posidonia oceanica is the most important marine phanerogam of the Mediterranean Sea due to its meadows’ complexity, persistence, and extension. These habitats provide a suite of ecosystem goods and services, being of primary importance in marine conservation. Despite their central role in the coastal ecology, P. oceanica meadows are undergoing overall deterioration and fragmentation in the basin mostly due to anthropogenic impacts at local to global scales. In the last decades, several management measures have been proposed aiming to improve the meadow health conditions, while the periodic monitoring of P. oceanica meadows allows for verifying their effectiveness. Here, we report the results of the monitoring of P. oceanica at Tremiti Islands Marine Protected Area (Adriatic Sea, Italy) carried out in 2003, 2015, and 2020. A general worsening was observed, particularly enhanced by direct anthropogenic impacts mostly related to anchoring practices, as well as by a certain level of sedimentation possibly deriving from coastal development. However, the identification of these impacts and the correct management of human activities to mitigate them produced positive results in a relatively short time span. Abstract: Posidonia oceanica meadows are Mediterranean coastal habitats of great conservation importance. This study is focused on a meadow located at Tremiti Islands Marine Protected Area (Adriatic Sea, Italy), which was monitored in 2003, 2015, and 2020 to evaluate its health state over time in relation to coastal human activities, which have been highly affecting this MPA for the last 20 years. To assess any change in the physiognomy of the meadow, rhizome density, percentage coverage, and lower limit progressions and/or regression over time were evaluated by scuba diving, while the distribution and extension of the meadow were assessed through habitat mapping using a side-scan sonar. Moreover, phenological and lepidochronological analyses were performed on the collected rhizomes to assess the leaf area index (LAI, m2m2) and the rhizome age (lepidochronological years). Our study showed a general deterioration of P. oceanica meadow from 2003 to 2020, with a significant reduction of its absolute and relative rhizome density and LAI at almost all sampling stations, absence of renovation of the meadow, and lower limit regression and overall worsening of the main conservation status indicators. However, appropriate management actions, such as the establishment of mooring buoy fields, supported the improvement of the P. oceanica status at the local scale with a significant increase in density and LAI and the presence of active stolonization processes, suggesting that mitigation actions can play a crucial role in the conservation of this habitat. On the contrary, local anthropogenic impacts, especially anchoring and coastal development, markedly affect the resilience of P. oceanica meadows to global stressors, such as climate change
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