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The Strait of Bonifacio is a long and narrow area between Corsica and Sardinia. To manage environmental emergencies related to the spill of oil from vessels, an innovative forecasting system was developed. This tool is capable of operationally predicting the dispersion of hydrocarbon spills in the coastal area of the Bonifacio Strait, either from an instantaneous or continuous spill and either in forward or backward mode. Experimental datasets, including ADCP water current measurements and the trajectories of drifter buoys released in the area, were used to evaluate the accuracy of this system. A comparison between the simulation results and experimental data revealed that both the water circulation and the surface transport processes are accurately reproduced by the model. The overall accuracy of the system in reproducing the transport of an oil spill at sea was estimated for both forward and backward prediction mode and in relation to different forecasting time lags.

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In organic-enriched sedimentary systems, like many Mediterranean coastal lagoons, a detailed analysis of sediment grain size composition and partitioning within the muds is crucial to investigate sedimentological trends related to both hydrodynamic energy and basin morphology. In these systems, sediment dynamics are particularly important because the partitioning and transport of fine sediments can strongly influence the redistribution and accumulation of large amounts of organic matter, and consequently the distribution of benthic assemblages and the trophic status and functioning of a lagoon. Nevertheless, studies on benthic-sediment relationships have been based mainly on a rather coarse analysis of sediment grain size features. In muddy systems, however, this approach may impede a proper evaluation of the relationships and effects of the distribution of fine sediment and organic matter on the biotic benthic components. Here we show that the distribution of sedimentary organic matter (OM) and total organic carbon (TOC) in the Cabras lagoon (Sardinia, Italy) can be explained (i.e., predicted) as a function of a nonlinear increase in the amount of the cohesive fraction of sediments (< or = 8 microm grain size particles) and that this fraction strongly influences the structure, composition and distribution of macrobenthic assemblages. Even in such a homogeneously muddy system, characterized by "naturally" occurring impoverished communities, impaired benthic assemblages were found at < or = 8 microm, OM, TOC contents of about 77%, 11% and 3.5%, respectively. A review of studies conducted in Mediterranean coastal lagoons highlighted a lack of direct integrated analysis of sediment features and the biotic components. We suggest that, especially in organic-enriched coastal lagoons, monitoring programs should primarily investigate and consider the cohesive fraction of sediments in order to allow a better assessment of benthic-sediment relationships and ecological quality of the system.

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Angiogenesis, the formation of new capillary blood vessels, occurs almost exclusively in the microcirculation. This process is controlled by the interaction between factors with positive and negative regulatory activity. In this study, we have compared the effect of two well described positive regulators, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (FGF-2) on bovine adrenal cortex-derived microvascular endothelial (BME) and bovine aortic endothelial (BAE) cells. The parameters we assessed included (a) cellular reorganization and lumen formation following exposure of the apical cell surface to a three-dimensional collagen gel; (b) organization of the actin cytoskeleton; (c) expression of thrombospondin-1 (TSP-1), an endogenous negative regulator of angiogenesis; and (d) extracellular proteolytic activity mediated by the plasminogen activator (PA)/plasmin system. We found that (a) collagen gel overlay induces rapid reorganization and lumen formation in BME but not BAE cells; (b) FGF-2 but not VEGF induced dramatic reorganization of actin microfilaments in BME cells, with neither cytokine affecting BAE cells; (c) FGF-2 decreased TSP-1 protein and mRNA expression in BME cells, an effect which was specific for FGF-2 and BME cells, since TSP-1 protein levels were unaffected by VEGF in BME cells, or by FGF-2 or VEGF in BAE cells; (d) FGF-2 induced urokinase-type PA (uPA) in BME and BAE cells, while VEGF induced uPA and tissue-type PA in BME cells with no effect on BAE cells. Taken together, these findings reveal endothelial cell-type specific responses to FGF-2 and VEGF, and point to the greater specificity of these cytokines for endothelial cells of the microvasculature than for large vessel (aortic) endothelial cells. Furthermore, when viewed in the context of our previous observation on the synergistic interaction between VEGF and FGF-2, our present findings provide evidence for complementary mechanisms which, when acting in concert, might account for the synergistic effect.

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BACKGROUND: SF-12 is a generic short form health survey, developed in the USA from the original SF-36. It produces two summary measures evaluating physical and mental self-perceived health that are interchangeable with those from the SF-36. SF-12 has been successfully tested in nine Western European countries on large samples of the general population, where it has proved its brevity, comprehensiveness, reliability, validity and cross-cultural applicability. The present analysis directly assesses the SF-12 for the first time in various Italian settings, including the general population and specific patient groups. METHODS: Data for this report were collected from five different samples; in four of them the SF-12 was used as a 'stand-alone' instrument, while in the other one (used as the reference) it was embedded in the SF-36. Descriptive statistics, Spearman's correlation coefficients, confirmatory factor analysis, ordinal uni- and multi-variate least squares regression model and covariance analysis were used to evaluate the summary measures in each sample, and across relevant subgroups. Studies were ordered according to the expected deviance, from the 'normal' health status of the reference group to the sample with the expected highest level of illness. RESULTS: Overall, more than 11,000 subjects were evaluated. Response rates ranged from 63 to 100%, while missing items accounted only for 0.2-8.2% of all items. Uni- and multi-variate analyses showed a positive association between both physical component summary (PCS) and mental component summary (MCS) scores and their respective items in all examined samples. MCS scores were fairly similar across all samples, with the only exception being patients recently discharged from hospital, whose subjective mental health perception was higher than expected and the highest of all (52.2). Finally, we found a substantial impact of ageing on physical health perception, while the MCS was shown to be less sensitive to the age effect. CONCLUSIONS: This analysis shows that the SF-12 has good validity, while some issues related to its most appropriate mode of administration and target groups might require further attention.

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A murine endothelial cell line was recently established from microvessels that had invaded a subcutaneous sponge implant (Dong, Q. G.; Bernasconi, S.; Lostaglio, S., et al. Arterioscl. Thromb. Vasc. Biol. 17:1599-1604; 1997). From these sponge-induced endothelial (SIE) cells, we have isolated two subpopulations endowed with different phenotypic properties. Clone SIE-F consists of large, highly spread cells that have a relatively slow growth rate, form contact-inhibited monolayers, do not grow under anchorage-independent conditions, express elevated levels of thrombospondin-1 (TSP-1) and are not tumorigenic in vivo. In contrast, clone SIE-S2 consists of small, spindle-shaped cells that have a high proliferation rate, do not show contact-inhibition, grow under anchorage-independent conditions, express very low levels of TSP-1 and are tumorigenic in vivo. Both clones express the endothelial markers vascular endothelial-cadherin and vascular intercellular adhesion molecule-1, but do not express CD31 and E-selectin. In addition, SIE-S2 cells, but not SIE-F cells, express the alpha-smooth muscle actin isoform. SIE-S2 cells, but not SIE-F cells, are able to form branching tubes in fibrin gels. The SIE-F and SIE-S2 clones, which have properties of nontransformed and transformed cells, respectively, should provide useful tools to investigate physiological and pathological processes involving vascular endothelium.

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This study was performed in 97 hemodialysis patients (85 on HD and 12 on CAPD) to investigate the possible correlation between B2-m and hemodialysis-related amyloidosis syndromes (HRA-S); differences in B2-m and HRA behavior between patients hemodialysed with cellulose and synthetic membranes were also included in the present study. Data indicate that B2-m levels are not correlated with dialysis length or with the type of membrane used for the dialysis. On the contrary, in 16 patients with the Carpal Tunnel Syndrome, a significant correlation was found between the CTS, the dialysis length and the type of membrane (greater incidence with cellulosic membranes).

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Preliminary results are reported on the endo-vesical use of a complex of synthetic peptides ('Peptichemio') in 15 patients suffering from bladder neoplasia who were judged to be beyond surgery or radiotherapy. The agent was introduced into bladder in 20 mg doses diluted in 50 ml of 5% glucose and retained for approximately 30 minutes. Treatment was repeated every 5 to 7 days. The disappearance of the neoplastic mass in 13% of the cases and its reduction in a further 53% encourage the continued use of the preparation in local regional therapy of bladder neoplasia, and the findings help to establish treatment times and doses. For the moment, the authors recommend increasing the interval between treatments to 10 days or more once the neoplastic mass has been reduced or disappeared.

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