69 research outputs found

    Pharmacologically active microcarriers associated with thermosensitive hydrogel as a growth factor releasing biomimetic 3D scaffold for cardiac tissue-engineering

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    International audienceThe challenge of tissue engineering of the infarcted heart is how to improve stem cell engraftment, survival, homing, and differentiation for myocardial repair. We here propose to integrate human adipose-derived stem cells (ADSCs) and pharmacologically active microcarriers (PAMs), a three-dimensional (3D) carrier of cells and growth factors, into an injectable hydrogel (HG), to obtain a system that stimulates the survival and/or differentiation of the grafted cells toward a cardiac phenotype. PAMs are biodegradable and non-cytotoxic poly(lactic-co-glycolic acid) (PLGA) microspheres conveying cells on their 3D surface that deliver continuously and in a controlled manner a growth factor (GF) acting on the transported cells and on the microenvironment to improve engraftment. The choice of the appropriate GF and its protection during the formulation process and delivery are essential. In this study two GFs, hepatocyte growth factor (HGF) and insulin-like growth factor (IGF-1), have been encapsulated under a solid state in order to limit their interaction with the polymer and conserve their integrity. GF precipitation conditions and release profile from PAMs have been first investigated before combining them to ADSCs. The released IGF-1 and HGF induced the protein synthesis of cardiac differentiation markers GATA4, Nkx2.5, cTnI and CX43 after 1 week in vitro. Moreover, the GFs accelerated cell cycle progression, as suggested by the increased expression of Cyclin D1 mRNA and the widespread distribution of Ki67 protein. Integrating PAMs within the thermosensitive P407 hydrogel increased their elastic properties but decreased the transcription of most cardiac markers. In contrast, CX43 expression increased in ADSC–PAM–GF complexes embedded within the hydrogel compared to the ADSCs cultured alone in the absence of P407. These results suggest that particulate scaffolds releasing HGF and IGF-1 may be beneficial for applications in tissue-engineering strategies for myocardial repair and the association with a P407 hydrogel can increase substrate elasticity and junction connections in ADSCs

    A diastrophic dysplasia sulfate transporter (SLC26A2) mutant mouse: morphological and biochemical characterization of the resulting chondrodysplasia phenotype.

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    Mutations in the diastrophic dysplasia sulfate transporter (DTDST or SLC26A2) cause a family of recessively inherited chondrodysplasias including, in order of decreasing severity, achondrogenesis 1B, atelosteogenesis 2, diastrophic dysplasia (DTD) and recessive multiple epiphyseal dysplasia. The gene encodes a widely distributed sulfate/chloride antiporter of the cell membrane whose function is crucial for the uptake of inorganic sulfate, which is needed for proteoglycan sulfation. To provide new insights in the pathogenetic mechanisms leading to skeletal and connective tissue dysplasia and to obtain an in vivo model for therapeutic approaches to DTD, we generated a Dtdst knock-in mouse with a partial loss of function of the sulfate transporter. In addition, the intronic neomycine cassette in the mutant allele contributed to the hypomorphic phenotype by inducing abnormal splicing. Homozygous mutant mice were characterized by growth retardation, skeletal dysplasia and joint contractures, thereby recapitulating essential aspects of the DTD phenotype in man. The skeletal phenotype included reduced toluidine blue staining of cartilage, chondrocytes of irregular size, delay in the formation of the secondary ossification center and osteoporosis of long bones. Impaired sulfate uptake was demonstrated in chondrocytes, osteoblasts and fibroblasts. In spite of the generalized nature of the sulfate uptake defect, significant proteoglycan undersulfation was detected only in cartilage. Chondrocyte proliferation and apoptosis studies suggested that reduced proliferation and/or lack of terminal chondrocyte differentiation might contribute to reduced bone growth. The similarity with human DTD makes this mouse strain a useful model to explore pathogenetic and therapeutic aspects of DTDST-related disorders

    Enhanced engraftment and repairing ability of human adipose-derived stem cells, conveyed by pharmacologically active microcarriers continuously releasing HGF and IGF-1, in healing myocardial infarction in rats

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    One of the main cause of ineffective cell therapy in repairing the damaged heart is the poor yield of grafted cells. To overcome this drawback, rats with 4-week-old myocardial infarction (MI) were injected in the border zone with human adipose-derived stem cells (ADSCs) conveyed by poly(lactic-co-glycolic acid) microcarriers (PAMs) releasing hepatocyte growth factor (HGF) and insulin-like growth factor-1 (IGF-1) (GFsPAMs). According to treatments, animals were subdivided into different groups: MI_ADSC, MI_ADSC/PAM, MI_GFsPAM, MI_ADSC/GFsPAM, and untreated MI_V. Two weeks after injection, a 31% increase in ADSC engraftment was observed in MI_ADSC/PAM compared with MI_ADSC (p < 0.05). A further ADSC retention was obtained in MI_ADSC/GFsPAM with respect to MI_ADSC (106%, p < 0.05) and MI_ADSC/PAM (57%, p < 0.05). A 130% higher density of blood vessels of medium size was present in MI_ADSC/GFsPAM compared with MI_ADSC (p < 0.01). MI_ADSC/GFsPAM also improved, albeit slightly, left ventricular remodeling and hemodynamics with respect to the other groups. Notably, ADSCs and/or PAMs, with or without HGF/IGF-1, trended to induce arrhythmias in electrically driven, Langendorff-perfused, hearts of all groups. Thus, PAMs releasing HGF/IGF-1 markedly increase ADSC engraftment 2 weeks after injection and stimulate healing in chronically infarcted myocardium, but attention should be paid to potentially negative electrophysiological consequences

    A meta-analysis of genome-wide association studies of epigenetic age acceleration

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    Funding: Generation Scotland received core support from the Chief Scientist Office of the Scottish Government Health Directorates (CZD/16/6) and the Scottish Funding Council (HR03006). Genotyping and DNA methylation profiling of the GS samples was carried out by the Genetics Core Laboratory at the Wellcome Trust Clinical Research Facility, Edinburgh, Scotland and was funded by the Medical Research Council UK and the Wellcome Trust (Wellcome Trust Strategic Award “STratifying Resilience and Depression Longitudinally” ((STRADL) Reference 104036/Z/14/Z)). Funding details for the cohorts included in the study by Lu et al. (2018) can be found in their publication. HCW is supported by a JMAS SIM fellowship from the Royal College of Physicians of Edinburgh and by an ESAT College Fellowship from the University of Edinburgh. AMM & HCW acknowledge the support of the Dr. Mortimer and Theresa Sackler Foundation. SH acknowledges support from grant 1U01AG060908-01. REM is supported by Alzheimer’s Research UK major project grant ARUK-PG2017B-10. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Data Availability: Summary statistics from the research reported in the manuscript will be made available immediately following publication on the Edinburgh Data Share portal with a permanent digital object identifier (DOI). According to the terms of consent for Generation Scotland participants, requests for access to the individual-level data must be reviewed by the GS Access Committee ([email protected]). Individual-level data are not immediately available, due to confidentiality considerations and our legal obligation to protect personal information. These data will, however, be made available upon request and after review by the GS access committee, once ethical and data governance concerns regarding personal data have been addressed by the receiving institution through a Data Transfer Agreement.Peer reviewedPublisher PD

    Monitoraggio di PM2.5 e PM1 campionati in prossimità del termovalorizzatore di Rifiuti Solidi Urbani di Bologna

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    La Regione Emilia-Romagna ha promosso una ricerca applicata chiamata Progetto Moniter (http://www.moniter.it). Uno degli obiettivi di progetto è stato quello di effettuare una campagna di monitoraggio allo scopo di acquisire nuove conoscenze della qualità dell‟aria in prossimità di un termovalorizzatore. Per fare questo sono state realizzate due campagne di monitoraggio in prossimità di un impianto con le seguenti caratteristiche: 600 tonnellate/giorno di capacità di incenerimento, due camini alti 80 metri e le migliori tecnologie disponibili per l‟abbattimento degli inquinanti, come da legislazione IPPC D.Lgs. 59/2005. La prima campagna è stata effettuata nell‟estate del 2008 e la seconda nell‟inverno del 2009. L‟impianto è posizionato in un‟area suburbana-rurale in prossimità di Bologna. Sono state installate otto stazioni di monitoraggio, una nel sito di background urbano e le altre sette in un dominio di 8x9 km2 intorno all‟impianto. Per il posizionamento delle stazioni è stato effettuato uno studio con un modello di dispersione gaussiano modificato (ADMS-Urban, CERC, Cambridge, UK), utilizzando le emissioni di PM10 come tracciante dell‟inquinamento [1]. Una prima stazione (MXW), che rappresenta una delle zone di alta ricaduta delle emissioni, è stata posizionata ad est dell‟impianto, lungo l‟asse della direzione principale dei venti; una seconda stazione (CTW), utilizzata come “controllo” della prima, è stata posizionata in un‟area interessata da una trascurabile ricaduta dovuta all‟impianto, ma avente un valore medio di tutte le immissioni extra-inceneritore simile a quello calcolato nel punto MXW. Con lo stesso principio sono state individuate altre due stazioni (MXS e CTS), con MXS posizionato ad ovest dell‟impianto. Le altre stazioni rappresentano differenti condizioni della qualità dell‟aria presenti nel dominio: MXD è un sito di alto traffico (situato nell‟area di più elevato inquinamento secondo la simulazione preliminare); MND è un sito rurale (situato nella zona di minimo inquinamento secondo la simulazione preliminare); CAS è rappresentativo di un'area suburbana. GMA, posizionato fuori dal dominio e nell‟area dei Giardini Margherita, rappresenta il fondo urbano. Le campagne Moniter hanno riguardato l'analisi di più di 130 specie chimiche. I dati sono stati processati con metodi statistici multivariati (PCA e Cluster Analysis), e i risultati di tali elaborazioni sono illustrati nel presente lavoro

    Le ricadute degli inceneritori sull'ambiente. Volume 1

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    In questo volume sono raccolti i risultati delle elaborazione dei dati sperimentali ottenuti delle analisi chimiche del particolato atmosferico raccolto in diversi siti di monitoraggio in vasto dominio della provincia di Bologna in cui è compreso l'impianto di incenerimento del Frullo

    Automatic detection of atmospheric boundary layer height using lidar backscatter data assisted by a boundary layer model

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    This work tackles the problem of the automated detection of the atmospheric boundary layer (BL) height h, from aerosol lidar/ceilometer observations. A new method, the Bayesian selective method (BSM), is presented. It implements a Bayesian statistical inference procedure which combines in a statistically optimal way different sources of information. Firstly, atmospheric stratification boundaries are located from discontinuities in the ceilometer backscattered signal. The BSM then identifies the discontinuity edge that has the highest probability to effectively mark the BL height. Information from the contemporaneous physical boundary layer model simulations and a climatological dataset of BL height evolution are combined in the assimilation framework to assist this choice. The BSM algorithm has been tested for 4 months of continuous ceilometer measurements collected during the BASE: ALFA project, and is shown to realistically diagnose the BL depth evolution in many different weather conditions. A standard one-dimensional processing of the ceilometer signal without the a priori support of the dynamical and climatological BL models often fails to correctly detect h, with the greatest inaccuracies occurring at night-time when residual layers can generate very strong signals, which are then classified by an automated application of the gradient or of the wavelet analysis as the most probable BL height. The BSM approach instead carries information on the low climatological probability to find elevated BL depths at night and penalizes the selection of these points. Moreover, this method is able to correctly convey information along the temporal dimension, thus filling data gaps using earlier and subsequent ceilometer information for the retrieva

    A 6-year analysis of stratospheric intrusions and their influence on ozone at Mt. Cimone (2165 m above sea level)

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    In this paper we present a study on stratospheric intrusion (SI) events recorded at a high mountain station in the Italian northern Apennines. Six years (1998–2003) of surface ozone and beryllium-7 concentration measurements as well as relative humidity values recorded at the GAW Mt. Cimone research station (44110N, 10420E; 2165 m asl) were analyzed. Moreover, three-dimensional backward trajectories calculated by the FLEXTRA model and potential vorticity values along these trajectories were used. In order to identify SI and evaluate their contribution to the tropospheric ozone at Mt. Cimone, a statistical methodology was developed. This methodology consists of different selection criteria based on observed and modeled stratospheric tracers as well as on tropopause height values recorded by radio soundings. On average, SI effects affected Mt. Cimone for about 36 days/year. The obtained 6-year SI climatology showed a clear seasonal cycle with a winter maximum and a spring-summer minimum. The seasonal cycle was also characterized by an interannual variation. In particular, during winter (autumn), SI frequency could be related to the intensity of the positive (negative) NAO phase. In order to separate direct SI from indirect SI, a restrictive selection criterion was set. This criterion, named Direct Intrusion Criterion (DIC), requested that all the analyzed tracers were characterized by stratospheric values. Direct SI affected Mt. Cimone for about 6 days/year, with frequency peaks in winter and early summer. At Mt. Cimone, SI contribution to background ozone concentrations was largest in winter. On average, an ozone increase of 8% (3%) with respect to the monthly running mean was found during direct (indirect) SI. Finally, the typical variations of stratospheric tracers during SI events were analyzed. The analysis of in situ atmospheric pressure values suggested that direct SI were connected with intense fronts affecting the region, while indirect SI were possibly connected with subsiding structures related with anticyclonic areas
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