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COVID-19 lockdown brought to a drastic reduction of anthropic impacts on the environment worldwide, including the marine-coastal system. Earth-Observation (EO) data have the potential to monitor and diagnose the effects of the lockdown in terms of water quality. Here we connect the dots among some coastal environmental changes that occurred during the Italian COVID-19 lockdown by using EO data, also seeking to assess connectivity between inland and marine systems. We present a holistic analysis of spatial and temporal variability of environmental parameters in the North Adriatic Sea, Mediterranean basin, exploiting the synergy of different satellite sensors, as well as hydrologic data from in situ observations. Our analysis indicates a favourable interplay of environmental variability that resulted in negative anomalies of Chlorophyll-a concentration, with respect to the climatologic values. Peculiar meteo-oceanographic and hydrological conditions made hard to disentangle potential anthropogenic effects. However, a multi-year hierarchical cluster analysis of riverine remote sensing reflectances groups together the optical properties of inland waters during the lockdown. This emergent cluster highlights the possibility of a second-order, anthropogenic effect that, superimposed to the (first-order) environmental natural causes, may have enhanced water quality during the lockdown., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

The fast spread of SARS-CoV-2 virus in Italy resulted in a 3-months lockdown of the entire country. During this period, the effect of the relieved anthropogenic activities on the environment was plainly clear all over the country. Herein, we provide the first evidence of the lockdown effects on riverine dissolved organic matter (DOM) dynamics. The strong reduction in anthropogenic activities resulted in a marked decrease in dissolved organic carbon (DOC) concentration in the Arno River (-44%) and the coastal area affected by its input (-15%), compared to previous conditions. The DOM optical properties (absorption and fluorescence) showed a change in its quality, with a shift toward smaller and less aromatic molecules during the lockdown. The reduced human activity and the consequent change in DOM dynamics affected the abundance and annual dynamics of heterotrophic prokaryotes. The results of this study highlight the extent to which DOM dynamics in small rivers is affected by secondary and tertiary human activities as well as the quite short time scales to return to the impacted conditions. Our work also supports the importance of long-term research to disentangle the effects of casual events from the natural variability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier B.V.)

In this study we analysed total mercury (THg) levels in European hake (Merluccius merluccius) - an ecologically and commercially important species throughout the Mediterranean - caught in the northern and central Adriatic Sea. To the best of our knowledge, this is the first study evaluating THg levels in hake fillets in relation to ecological (season) and biological (body size, sex, sexual maturity, lipid content) parameters. THg levels in muscle showed no sex-related differences; in contrast, significant season-related differences were found in females, with higher levels in spring-summer compared with autumn-winter. No season-related differences were seen in males. A significant sex effect was found for body size and sexual maturity. Females showed a correlation between THg level and length, THg being significantly higher in mature compared with immature specimens. No significant sex effect was found for muscle lipid content, because a correlation between THg concentration and tissue lipids was found in both sexes. Since the mean THg concentration found in M. merluccius fillets (0.64 ± 0.29 mg kg -1 dry weight; range, 0.20-1.53) was consistently under the level set by EU regulations, this study demonstrates that European hake caught in the northern and central Adriatic is safe for human consumption., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

MOON (Mediterranean Operational Oceanography Network http://www.moon-oceanforecasting.eu) provides near-real-time information on oil-spill detection (ocean color and SAR) and predictions [ocean forecasts (MFS and CYCOFOS) and oil-spill predictions (MEDSLIK)]. We employ this system to study the Lebanese oil-pollution crisis in summer 2006 and thus to assist regional and local decision makers in Europe, regionally and locally. The MEDSLIK oil-spill predictions obtained using CYCOFOS high-resolution ocean fields are compared with those obtained using lower-resolution MFS hydrodynamics, and both are validated against satellite observations. The predicted beached oil distributions along the Lebanese and Syrian coasts are compared with in situ observations. The oil-spill predictions are able to simulate the northward movement of the oil spill, with the CYCOFOS predictions being in better agreement with satellite observations. Among the free MEDSLIK parameters tested in the sensitivity experiments, the drift factor appears to be the most relevant to improve the quality of the results., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

It has been previously shown that fibrinogen (FG) associates specifically with human umbilical vein and bovine aortic endothelial cells (EC) in culture and induces EC migration. In the present study, we have investigated whether the FG-EC interaction is mediated by an Arg-Gly-Asp (RGD) recognition specificity and whether EC membrane proteins related to platelet GPIIb-IIIa are involved. Highly purified radioiodinated human FG, containing no detectable fibronectin, interacted with cultured human and bovine EC in suspension in a time-dependent and specific manner. The binding was inhibited by EDTA. Two polyclonal antibodies to platelet GPIIb-IIIa, which immunoprecipitated a heterodimer molecule from EC, inhibited FG binding to EC. These same antibodies inhibited FG-induced EC migration in a dose-dependent manner as measured in a Boyden chamber. Preabsorption of the antibodies with purified platelet GPIIb-IIIa markedly reduced both inhibitory activities. A series of synthetic RGD-containing peptides inhibited FG binding to EC and FG-induced EC migration. Gly-Arg-Gly-Asp (GRGD) was the most active peptide tested in inhibiting FG binding and EC migration (ID50 of 30 microM), and conservative substitutions in the RGD sequence markedly reduced inhibitory activity (ID50 greater than 1,000 microM). These results indicate that FG binding and EC migration are events mediated by an RGD recognition specificity and that EC surface proteins immunologically related to the GPIIb-IIIa complex on platelets are involved in this recognition.

Previous studies have shown that human endothelial cells (ECs) adhere to fibrinogen (fg) and fibronectin (fn) and organize their cytoskeleton on these substrata. However, the mechanism governing this chain of events is poorly known. In ECs glycoproteins immunologically and biochemically similar to the platelet membrane GpIIb-IIIa complex have been described. The functional role of this complex in ECs remains to be established. In this study we show that the antigens recognized by polyclonal antibodies raised against human platelet GpIIb-IIIa and crossreacting with the EC form have a discrete and well-organized distribution at cell adhesion structures. Indeed these antigens are located at vinculin-rich focal contacts found at the membrane insertion of microfilament bundles of the stress fiber type. They are also found at cell-to-cell contacts and, with a diffuse pattern, at the dorsal surface of ECs. GpIIb-IIIa antibodies, added to EC suspensions prior to plating, inhibit EC spreading on fg and vitronectin (vn) substrata in a concentration-dependent way. In contrast, the antibodies are very poorly active when the cells are seeded on fn-coated glass. The same antibodies, added to adherent cells, disrupt cell-to-cell contacts and cause their rounding and detachment. Overall these results indicate that EC GpIIb-IIIa complex is involved in controlling the adhesion mechanism of these cells to extracellular matrix proteins.

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) induced migration across polycarbonate filters of human polymorphonuclear leukocytes (PMN). rhG-CSF was active in inducing PMN migration at concentrations greater than or equal to 10 to 100 U/mL (7 to 70 ng/mL). rhG-CSF did not contain appreciable levels of endotoxin contamination as assessed by Limulus amebocyte assay, and Polymixin B did not affect the chemotactic activity of rhG-CSF. A monoclonal anti-G-CSF antibody blocked the induction of migration by G-CSF, thus establishing that the cytokine was responsible for the activity of the recombinant preparation. Checkerboard analysis was performed by seeding different concentrations of G-CSF above and/or below the filter and revealed that the migratory response to this cytokine was best observed in the presence of a positive concentration gradient between the lower and upper compartments of the chamber, thus indicating an actual chemotactic effect. When different migrating cells were examined, rhG-CSF was inactive on large granular lymphocytes and endothelial cells under conditions in which appropriate reference attractants were active. In contrast, rhG-CSF elicited a chemotactic response in monocytes inhibited by specific antibody. Thus, G-CSF is a chemotactic signal for phagocytes. This cytokine, when produced at inflammatory sites, may contribute to the recruitment of phagocytes from the blood compartment to amplify resistance against certain noxious agents.

In this study we provide a characterization of the fibronectin (FN) binding to endothelial cells (EC), and we identify the FN binding site on these cells. 125I-FN binding to EC in suspension was time dependent and reached a plateau at 4 h. Cold FN inhibited this interaction in a concentration-dependent way, but vitronectin, fibrinogen, and IgG were poorly effective. About 80% of the total FN associated to EC at the equilibrium was specifically bound; of this, 60% was reversibly bound, while 20% appeared to be internalized. The FN binding was saturable and an apparent dissociation constant of about 0.23 x 10(-6) mol/L and a maximal number of binding sites of about 9.8 x 10(5) was estimated from binding isotherms. Autoradiography data showed that EC-associated 125I-FN was all in high mol wt form that did not enter the gel. We then characterize the FN receptor (FNR) in EC. An antiserum to the FNR isolated from human placenta inhibited FN binding to EC by 89%, and using the immunoblotting technique, it recognized two bands in the EC detergent extract of mol wt 125/160 Kd. This antiserum also recognized the EC membrane protein complex eluted from the FN affinity column by an arg-gly-asp (RGD) peptide. When this complex was included into liposomes, it poorly bound to FN. However, the binding was strikingly increased by addition of Mn in the buffer and was specific for FN in respect to other substrata. These data define the FN binding site in EC and indicate that it is functionally and structurally related to that isolated from human placenta.