155 research outputs found

    Metal free graphene oxide (GO) nanosheets and pristine-single wall carbon nanotubes (p-SWCNTs) biocompatibility investigation: a comparative study in different human cell lines

    Get PDF
    The in vitro biocompatibility of Graphene Oxide (GO) nanosheets, which were obtained by the electrochemical exfoliation of graphite electrodes in an electrolytic bath containing salts, was compared with the pristine Single Wall Carbon Nanotubes (p-SWCNTs) under the same experimental conditions in different human cell lines. The cells were treated with different concentrations of GO and SWCNTs for up to 48 h. GO did not induce any significant morphological or functional modifications (demonstrating a high biocompatibility), while SWNCTs were toxic at any concentration used after a few hours of treatment. The cell viability or cytotoxicity were detected by the trypan blue assay and the lactate dehydrogenase LDH quantitative enzymatic test. The Confocal Laser Scanning Microscopy (CLSM) and transmission electron microscopy (TEM) analysis demonstrated the uptake and internalization of GO sheets into cells, which was localized mainly in the cytoplasm. Different results were observed in the same cell lines treated with p-SWCNTs. TEM and CLSM (Confocal Laser Scanning Microscopy) showed that the p-SWCNTs induced vacuolization in the cytoplasm, disruption of cellular architecture and damage to the nuclei. The most important result of this study is our finding of a higher GO biocompatibility compared to the p-SWCNTs in the same cell lines. This means that GO nanosheets, which are obtained by the electrochemical exfoliation of a graphite-based electrode (carried out in saline solutions or other physiological working media) could represent an eligible nanocarrier for drug delivery, gene transfection and molecular cell imaging tests

    MaxHadoop: An Efficient Scalable Emulation Tool to Test SDN Protocols in Emulated Hadoop Environments

    Get PDF
    AbstractThis paper presents MaxHadoop, a flexible and scalable emulation tool, which allows the efficient and accurate emulation of Hadoop environments over Software Defined Networks (SDNs). Hadoop has been designed to manage endless data-streams over networks, making it a tailored candidate to support the new class of network services belonging to Big Data. The development of Hadoop is contemporary with the evolution of networks towards the new architectures "Software Defined." To create our emulation environment, tailored to SDNs, we employ MaxiNet, given its capability of emulating large-scale SDNs. We make it possible to emulate realistic Hadoop scenarios on large-scale SDNs using low-cost commodity hardware, by resolving a few key limitations of MaxiNet through appropriate configuration settings. We validate the MaxHadoop emulator by executing two benchmarks, namely WordCount and TeraSort, to evaluate a set of Key Performance Indicators. The tests' outcomes evidence that MaxHadoop outperforms other existing emulation tools running over commodity hardware. Finally, we show the potentiality of MaxHadoop by utilizing it to perform a comparison of SDN-based network protocols

    Insights into vertebrate head development: From cranial neural crest to the modelling of neurocristopathies

    Get PDF
    Although the vertebrate head has evolved to a wide collection of adaptive shapes, the fundamental signalling pathways and cellular events that outline the head skeleton have proven to be highly conserved. This conservation suggests that major morphological differences are due to changes in differentiation and morphogenetic programs downstream of a well-maintained developmental prepattern. Here we provide a brief examination of the mechanisms and pathways responsible for vertebrate head development, as well as an overview of the animal models suitable for studying face development. In addition, we describe the criteria for neurocristopathy classifica-tion, highlighting the contribution of zebrafish to the modelling of Treacher Collins/Franceschetti Syndrome, an emblematic neurocristopathy. The contributions from our laboratory reveal that proper zebrafish head development depends on the fine-tuning of developmental-gene expression mediated by nucleic acid binding proteins able to regulate DNA conformation and / or the neuroepithelium redox state.Fil: Weiner, Andrea Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Coux, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Armas, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Calcaterra, Nora Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentin

    What's new about CNBP? Divergent functions and activities for a conserved nucleic acid binding protein

    Get PDF
    Background: Cellular nucleic acid binding protein (CNBP) is a conserved single-stranded nucleic acid binding protein present in most eukaryotes, but not in plants. Expansions in the CNBP gene cause myotonic dystrophy type 2. Initially reported as a transcriptional regulator, CNBP was then also identified acting as a translational regulator. Scope of review: The focus of this review was to link the CNBP structural features and newly reported biochemical activities with the recently described biological functions, in the context of its pathological significance. Major conclusions: Several post-translational modifications affect CNBP subcellular localization and activity. CNBP participates in the transcriptional and translational regulation of a wide range of genes by remodeling single-stranded nucleic acid secondary structures and/or by modulating the activity of trans-acting factors. CNBP is required for proper neural crest and heart development, and plays a role in cell proliferation control. Besides, CNBP has been linked with neurodegenerative, inflammatory, and congenital diseases, as well as with tumor processes. General significance: This review provides an insight into the growing functions of CNBP in cell biology. A unique and robust mechanistic or biochemical connection among these roles has yet not been elucidated. However, the ability of CNBP to dynamically integrate signaling pathways and to act as nucleic acid chaperone may explain most of the roles and functions identified so far.Fil: Armas, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Coux, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Weiner, Andrea Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Calcaterra, Nora Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentin

    Right ventricular diastolic function in post-surgical Tetralogy of Fallot patients: A pilot study to make a comparison between echocardiography and cardiac MRI

    Get PDF
    Background: right ventricular (RV) systolic dysfunction is associated with poor outcomes in Tetralogy of Fallot (ToF) patients. Conversely, the influence of diastolic dysfunction in this setting is poorly known. In addition, evaluation of RV diastolic function by cardiac MRI is rarely performed.Materials and methods: twenty-four surgically treated ToF patients were enrolled in the study (54% males; median age at study: 28 (18–50) years; median age at surgery: 1.9 (0.4–8.2) years. They were studied by echocardiography to assess RV diastolic function in terms of traditional and TDI-derived parameters. At cardiac MRI, RV diastolic function was assessed by using phase-contrast analysis of flow through the tricuspid valve in short axis view. Diastolic dysfunction was graded as impaired relaxation, pseudo-normal, or restrictive physiology.Results: fifteen (62.5%) ToF subjects had echocardiographic evidence of diastolic dysfunction and eleven (45.8%) at cardiac MRI. Statistically significant correlation between echocardiographic and cardiac MRI parameters of diastolic dysfunction was weak (p < 0.05). The degree of RV diastolic dysfunction (expressed as E/E' at TDI) was associated with right atrial volume indexed for body surface area at cardiac MRI (p < 0.0001). Greater number of interim palliative procedures was associated with higher E/E' (RV diastolic dysfunction) at echocardiography (p < 0.0003).Conclusions: diastolic dysfunction, as determined by echocardiography and cardiac MRI-derived measures, is prevalent in ToF. These measures are weakly associated with each other. Notwithstanding the limitations of this pilot study, the development of cardiac MRI parameters capable of correlating with RV relaxation is needed in ToF setting

    Conservation of Zebrafish MicroRNA-145 and Its Role during Neural Crest Cell Development

    Get PDF
    The neural crest is a multipotent cell population that develops from the dorsal neural fold of vertebrate embryos in order to migrate extensively and differentiate into a variety of tissues. A number of gene regulatory networks coordinating neural crest cell specification and differentiation have been extensively studied to date. Although several publications suggest a common role for microRNA-145 (miR-145) in molecular reprogramming for cell cycle regulation and/or cellular differentiation, little is known about its role during in vivo cranial neural crest development. By modifying miR-145 levels in zebrafish embryos, abnormal craniofacial development and aberrant pigmentation phenotypes were detected. By whole-mount in situ hybridization, changes in expression patterns of col2a1a and Sry-related HMG box (Sox) transcription factors sox9a and sox9b were observed in overexpressed miR-145 embryos. In agreement, zebrafish sox9b expression was downregulated by miR-145 overexpression. In silico and in vivo analysis of the sox9b 3′UTR revealed a conserved potential miR-145 binding site likely involved in its post-transcriptional regulation. Based on these findings, we speculate that miR-145 participates in the gene regulatory network governing zebrafish chondrocyte differentiation by controlling sox9b expressionThis research was funded by a CONICET External Grant (March 2018 to A.M.J.W.), an ANPCyT PICT Grant (PICT-2017-0509 to A.M.J.W.), and a CONICET PIP Grant (PIP-2015-0719 to N.B.C.)S

    Evaluation of the applicability of sediment transport models to dam filling prediction in different Italian geological contexts

    Get PDF
    Artificial reservoirs are crucial infrastructures, since they allow for the management of the water resource they store and for their role in the hydroelectric production. Water is modulated and stored inside artificial basins built upstream of the dams for hydroelectric, industrial, drinking, irrigation, and flood mitigation purposes. However, as time passes, the deposition of solid material, transported by rivers flowing into the reservoir, reduces its storage capacity. In this work, a novel physicallybased erosion and sediment transport model developed by Politecnico di Milano (SMART-SED) is used to estimate dam filling in different Italian geological contexts. The present model differs from others in the literature since it can automatically detect drainage zones and it works at a basin scale, requiring few input parameters that can be easily downloaded from global or government databases. Moreover, it is based on robust and unconditionally stable numerical techniques, and it guarantees the mass conservation. The proposed model was applied to four watersheds, two in the Southern Alps and two in the Southern Apennines, with catchment areas ranging from 5 to 48 km2. After the model calibration on the local geological context, a validation of the obtained results was accomplished considering different time intervals and the available sediment filling data. It was observed that the SMART-SED model, initially developed for the evaluation of fluvial hazard and of sediment transport in mountainous areas, was also suitable for the estimation of dam filling. Results indeed show a precise approximation of the order of magnitude of the cumulative sediment volume produced inside the catchments and transported to the water basins. In the framework of a complex problem affecting the production of “clean” energy in a changing world, SMART-SED could become a useful tool also for dam management
    • …
    corecore