Determinazione di mercurio mediante DMA-80

I fenomeni di contaminazione antropica da mercurio sono sempre più diffusi e preoccupanti, tanto da spingere all’ attivazione di politiche nazionali ed internazionali atte a ridurre o almeno “contenere” i rischi legati a questo metallo tossico. Con quest’obiettivo è prioritaria la necessità di determinare la concentrazione del metallo in maniera veloce, economica ed efficiente. Il seguente report intende fornire informazioni utili nell’utilizzo dello spettrofotometro DMA-80 nell’analisi di Hg in varie matrici ambientali. Lo strumento è stato acquistato dall’IAMC-CNR di Capo Granitola per rispondere alle esigenze progettuali del progetto “Dinamica dei processi di evasione e deposizione del mercurio nell’area industrializzata della Rada di Augusta e definizioni delle mappe di rischio sanitario per le popolazioni residenti” (prot.n°0000466 18/2/2011) finanziato dall’Assessorato alla Salute della Regione Sicilia con l’obbiettivo di verificare il potenziale impatto del mercurio, derivato dalle emissioni dei reflui non trattati dell’impianto di cloro-soda SYNDIAL Priolo-Gargallo sulle popolazioni residenti nell’aria fortemente industrializzata di Augusta-Melilli (Siracusa)

Transforming growth factor β (CiTGF-β) gene expression is induced in the inflammatory reaction of Ciona intestinalis

Transforming growth factor (TGF-β) is a well-known component of a regulatory cytokines superfamily that has pleiotropic functions in a broad range of cell types and is involved, in vertebrates, in numerous physiological and pathological processes. In the current study, we report on Ciona intestinalis molecular characterisation and expression of a transforming growth factor β homologue (CiTGF-β). The gene organisation, phylogenetic tree and modelling supported the close relationship with the mammalian TGF suggesting that the C. intestinalis TGF-β gene shares a common ancestor in the chordate lineages. Functionally, real-time PCR analysis showed that CiTGF-β was transcriptionally upregulated in the inflammatory process induced by LPS inoculation, suggesting that is involved in the first phase and significant in the secondary phase of the inflammatory response in which cell differentiation occurs. In situ hybridisation assays revealed that the genes transcription was upregulated in the pharynx, the main organ of the ascidian immune system, and expressed by cluster of hemocytes inside the pharynx vessels. These data supported the view that CiTGF-β is a potential molecule in immune defence systems against bacterial infection

Experimental study of uni and bi-directional exchange flows in a large scale rotating trapezoidal channel

International audienceA large-scale experimental study has been conducted at the Coriolis Rotating Platform to investigate the dynamics of uni- and bi-directional exchange flows along a channel with a trapezoidal cross section under the influence of background rotation. High-resolution two-dimensional particle image velocimetry and micro-conductivity probes were used to obtain detailed velocity fields and density profiles of the exchange flow generated across the channel under different parametric conditions. Experimental measurements give new insight into the stratified-flow dynamics dependence on the magnitude of Burger number, defined as the ratio of the Rossby radius to the channel width, such that values lower than 0.5 characterize unsteady exchange flows. The measurements highlight the role that both ambient rotation and net-barotropic forcing have on the geostrophic adjustment of the dense outflowing layer and on the corresponding counter-flowing water layer fluxes. The coupled effect of these two parametric conditions largely affects the transverse velocity distribution and, for the largest net-barotropic flow in the upper fresh water layer, leads to the partial blockage of the lower saline outflow. Moreover, an increase in the mixing layer thickness, associated with larger rotation rates, and due the interface dynamics, is observed, with shear-driven interfacial instabilities analyzed to highlight the influence of both ambient rotation and net-barotropic forcin

Retinoic Acid Specifically Enhances Embryonic Stem Cell Metastate Marked by Zscan4

Pluripotency confers Embryonic Stem Cells (ESCs) the ability to differentiate in ectoderm, endoderm, and mesoderm derivatives, producing the majority of cell types. Although the majority of ESCs divide without losing pluripotency, it has become evident that ESCs culture consists of multiple cell populations with different degrees of potency that are spontaneously induced in regular ESC culture conditions. Zscan4, a key pluripotency factor, marks ESC subpopulation that is referred to as high-level of pluripotency metastate. Here, we report that in ESC cultures treated with retinoic acid (RA), Zscan4 ESCs metastate is strongly enhanced. In particular, we found that induction of Zscan4 metastate is mediated via RA receptors (RAR-alpha, RAR-beta, and RAR-gamma), and it is dependent on phosphoinositide-3-kinase (PI3K) signaling. Remarkably, Zscan4 metastate induced by RA lacks canonical pluripotency genes Oct3/4 and Nanog but retained both self-renewal and pluripotency capabilities. Finally we demonstrated that the conditional ablation of Zscan4 subpopulation is dispensable for both endoderm and mesoderm but is required for ectoderm lineage. In conclusion, our research provides new insights about the role of RA signaling during ESCs high pluripotency metastate fluctuation

The dynamics of bi-directional exchange flows

The global demand for low carbon electricity requires a variety of energy generation approaches, the choice of which is dependent on multiple criteria. Tidal flows have long been identified as a reliable source of energy, with a high degree of predictability. To this end a novel turbine has been developed that could be well suited to energy generation in both tidal flows, or water courses. In this study a Smoothed Particle Hydrodynamics (SPH) model, namely DualSPHysics, is used to predict the behavior of this novel turbine design. Which will be used to guide the design process. The SPH method was chosen as the design of the turbine uses several connected parts, that requires free movement and interactions to properly represent the prototype and was found to be capable of expressing this behavior

The dynamics of bi-directional exchange flows::implication for morphodynamic change within estuaries and sea straits

Environmental and geophysical flows, including dense bottom gravity currents in the ocean and buoyancy-driven exchange flows in marginal seas, are strongly controlled by topographic features. These are known to exert significant influence on both internal mixing and secondary circulations generated by these flows. In such cases, uni-directional or bi-directional exchange flows develop when horizontal density differences and/or pressure gradients are present between adjacent water bodies connected by a submerged channel. The flow dynamics of the dense lower layer depend primarily on the volumetric flux and channel cross-sectional shape, while the stratified interfacial flow mixing characteristics, leading to fluid entrainment/detrainment, are also dependent on the buoyancy flux and motion within the upper (lower density) water mass. For submerged channels that are relatively wide compared to the internal Rossby radius of deformation, Earth rotation effects introduce geostrophic adjustment of these internal fluid motions, which can suppress turbulent mixing generated at the interface and result in the development of Ekman layers that induce secondary, cross-channel circulations, even within straight channels. Moreover, recent studies of dense, gravity currents generated in rotating and non-rotating systems, respectively, indicated that the V-shaped channel topography had a strong influence on both flow distribution and associated interfacial mixing characteristics along the channel. However, such topographic controls on the interfacial mixing and secondary circulations generated by bi-directional exchange flows are not yet fully understood and remain to be investigated thoroughly in the laboratory. Also the effect of mobile bed for bi-directional exchange flows generated in deformable channels along with the physical interactions between the lower dense water flow and the erodible bed sediments will have a strong influence in (re-)shaping the overall channel bed topography (i.e. bed morphodynamics). Consequently, the resulting temporal changes in cross-sectional channel bathymetry (i.e. through erosion and deposition processes) would also be expected to have associated feedbacks on transverse asymmetries in the bi-directional exchange flow structure, as well as on the internal flow stability

A rare case of omental extra-gastrointestinal stromal tumor showing two coexisting mutations on exon 14 of the PDGFRA gene

Gastrointestinal stromal tumors (GISTs) are neoplasms arising from mesenchymal cells localized into the muscularis propria of the gastrointestinal (GI) tract [1]; 5% of GISTs are extra-GISTs (EGISTs), as they differently originate from adipose tissue adjacent to the GI tract (omentum and mesentery) or from the pancreas [2]. So far, both GISTs and EGISTs have been managed indistinctively by combining surgery, histopathological distinctive features, imaging, and molecular analysis. Moreover, despite the contribution of defined genetic backgrounds whose influence is acknowledged in this type of tumor (i.e. Carney’s triad or familiar form of GIST), the pathobiology of both GISTs and EGISTs is not yet fully understood. We describe an interesting case of an extensively diffuse EGIST involving only omentum and mesocolon with multinodular growth and peculiar histological features, and for which a deeper histopathological/ molecular analysis is reported. Case presentation A 74-year-old female with a historical diagnosis of multiple myeloma was referred for anemia, alvus disorders (diarrhea and constipation), weight loss (15 kg in 6 months), and palpable mass of the right flank that had appeared 8 weeks before. On medication for multiple myeloma since 2016 (melphalan combined with prednisone and bortezomib9; carfilzomib/lenalidomide/ desametasone6 until complete remission), she also had type II diabetes, treated with oral medications and open cholecystectomy in the 1980s. Physical examination revealed the presence of a large mobile non-painful mass in the right flank apparently from the right colon, without signs of occlusion or intestinal bleeding. Blood analysis showed: hemoglobin 7.9 g/dL, white blood cells 2.3103/lL, glycemia 191 mg/dL, and a low potassium level of 2.8 mEq/L. We first treated the glycemia by insulin infusion and, second, we investigated the signs of anemia. By lower GI Submitted: 14 May 2020; Revised: 20 July 2020; Accepted: 28 July 202

Susceptibility of Human Melanoma Cells to Autologous Natural Killer (NK) Cell Killing: HLA-Related Effector Mechanisms and Role of Unlicensed NK Cells

BACKGROUND: Despite Natural Killer (NK) cells were originally defined as effectors of spontaneous cytotoxicity against tumors, extremely limited information is so far available in humans on their capability of killing cancer cells in an autologous setting. METHODOLOGY/PRINCIPAL FINDINGS: We have established a series of primary melanoma cell lines from surgically resected specimens and here showed that human melanoma cells were highly susceptible to lysis by activated autologous NK cells. A variety of NK cell activating receptors were involved in killing: particularly, DNAM-1 and NKp46 were the most frequently involved. Since self HLA class I molecules normally play a protective role from NK cell-mediated attack, we analyzed HLA class I expression on melanomas in comparison to autologous lymphocytes. We found that melanoma cells presented specific allelic losses in 50% of the patients analyzed. In addition, CD107a degranulation assays applied to NK cells expressing a single inhibitory receptor, revealed that, even when expressed, specific HLA class I molecules are present on melanoma cell surface in amount often insufficient to inhibit NK cell cytotoxicity. Remarkably, upon activation, also the so called "unlicensed" NK cells, i.e. NK cells not expressing inhibitory receptor specific for self HLA class I molecules, acquired the capability of efficiently killing autologous melanoma cells, thus additionally contributing to the lysis by a mechanism independent of HLA class I expression on melanoma cells. CONCLUSIONS/SIGNIFICANCE: We have investigated in details the mechanisms controlling the recognition and lysis of melanoma cells by autologous NK cells. In these autologous settings, we demonstrated an efficient in vitro killing upon NK cell activation by mechanisms that may be related or not to abnormalities of HLA class I expression on melanoma cells. These findings should be taken into account in the design of novel immunotherapy approaches against melanoma

An Historical Overview: The Discovery of How NK Cells Can Kill Enemies, Recruit Defense Troops, and More

Natural killer (NK) cells were originally defined as effector lymphocytes of innate immunity characterized by the unique ability of killing tumor and virally infected cells without any prior priming and expansion of specific clones. The \u201cmissing-self\u201d theory, proposed by Klas Karre, the seminal discovery of the first prototypic HLA class I-specific inhibitory receptors, and, later, of the Natural Cytotoxicity Receptors (NCRs) by Alessandro Moretta, provided the bases to understand the puzzling behavior of NK cells. Actually, those discoveries proved crucial also for many of the achievements that, along the years, have contributed to the modern view of these cells. Indeed, NK cells, besides killing susceptible targets, are now known to functionally interact with different immune cells, sense pathogens using TLR, adapt their responses to the local environment, and, even, mount a sort of immunological memory. In this review, we will specifically focus on the main activating NK receptors and on their crucial role in the ever-increasing number of functions assigned to NK cells and other innate lymphoid cells (ILCs)