255 research outputs found

    Colorimetric paper-based device for hazardous compounds detection in air and water: A proof of concept

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    In the last decades, the increase in global industrialization and the consequent technological progress have damaged the quality of the environment. As a consequence, the high levels of hazardous compounds such as metals and gases released in the atmosphere and water, have raised several concerns about the health of living organisms. Today, many analytical techniques are available with the aim to detect pollutant chemical species. However, a lot of them are not affordable due to the expensive instrumentations, time-consuming processes and high reagents volumes. Last but not least, their use is exclusive to trained operators. Contrarily, colorimetric sensing devices, including paper-based devices, are easy to use, providing results in a short time, without particular specializations to interpret the results. In addition, the colorimetric response is suitable for fast detection, especially in resource-limited environments or underdeveloped countries. Among different chemical species, transition and heavy metals such as iron Fe(II) and copper Cu(II) as well as volatile compounds, such as ammonia (NH3) and acetaldehyde (C2 H4 O) are widespread mainly in industrialized geographical areas. In this work, we developed a colorimetric paper-based analytical device (PAD) to detect different contaminants, including Fe2+ and Cu2+ ions in water, and NH3 and C2 H4 O in air at low concentrations. This study is a “proof of concept” of a new paper sensor in which the intensity of the colorimetric response is proportional to the concentration of a detected pollutant species. The sensor model could be further implemented in other technologies, such as drones, individual protection devices or wearable apparatus to monitor the exposure to toxic species in both indoor and outdoor environments

    Estimations of length-weight relationships and consumption rates of odontocetes in the Mediterranean Sea from stranding data

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    Stranding data provide fundamental information on biometric traits of cetaceans useful to increase knowledge on ecological traits and their consumption patterns. In this study, the length weight (L-W) relationships through the power regression model (W = a ×Lb ) were calculated for three dolphin species (the striped dolphin, the common bottlenose dolphin and the Risso’s dolphin) in several Mediterranean subregions and at the scale of the entire basin. Length (L) and weight (W) data were collected from stranding records during the period from 1983 to 2021 acquired from several databases and the literature. Starting from L-W relationships, a bootstrap method was applied to estimate the mean body weights, the daily ingested biomass (IB) and annual food consumption (AFC) rates of different dolphin species. In particular, four different equations were used to estimate the IB rates. Prey consumption by dolphin species was calculated through AFC rates and the available diet information (expressed in weight fractions) of dolphin species for different Mediterranean subregions. Considering the L-W relationships in the Mediterranean Sea, b coefficient values were equal to 2.578, 2.975 and 2.988 for the striped, the common bottlenose and the Risso’s dolphin, respectively. At the Mediterranean scale, the AFC values estimated were 3913 kg (CI 2469–5306) for the Risso’s dolphin, 2571 kg (1372–3963) for the common bottlenose dolphin and 1118 kg (531–1570) for the striped dolphin. Prey consumption pattern showed a clear partitioning among the investigated species, where the common bottlenose dolphin exploits neritic demersal and pelagic fishes (e.g. eel fishes, sparids), the striped dolphin exploits mesopelagic fishes and myctophids, and the Risso’s dolphin was specialized on bathyal cephalopods of Histioteuthidae family. The results obtained in this study provide new information for the investigated species in several Mediterranean subregions providing a first consistent baseline to support the population dynamics modelling. At the same time, the wide uncertainty ranges of some parameters, as well as the lack of information for some species, stress the necessity of improving the data collection associated to stranding events, especially in the southern Mediterranean areas

    Physico-chemical properties of inorganic nps influence the absorption rate of aquatic mosses reducing cytotoxicity on intestinal epithelial barrier model

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    Noble metals nanoparticles (NPs) and metal oxide NPs are widely used in different fields of application and commercial products, exposing living organisms to their potential adverse effects. Recent evidences suggest their presence in the aquifers water and consequently in drinking water. In this work, we have carefully synthesized four types of NPs, namely, silver and gold NPs (Ag NPs and Au NPs) and silica and titanium dioxide NPs (SiO2 NPs and TiO2 NPs) having a similar size and negatively charged surfaces. The synthesis of Ag NPs and Au NPs was carried out by colloidal route using silver nitrate (AgNO3 ) and tetrachloroauric (III) acid (HAuCl4 ) while SiO2 NPs and TiO2 NPs were achieved by ternary microemulsion and sol-gel routes, respectively. Once the characterization of NPs was carried out in order to assess their physico-chemical properties, their impact on living cells was studied. We used the human colorectal adenocarcinoma cells (Caco-2), known as the best representative intestinal epithelial barrier model to understand the effects triggered by NPs through ingestion. Then, we moved to explore how water contamination caused by NPs can be lowered by the ability of three species of aquatic moss, namely, Leptodictyum riparium, Vesicularia ferriei, and Taxiphyllum barbieri, to absorb them. The experiments were conducted using two concentrations of NPs (100 µM and 500 Mm as metal content) and two time points (24 h and 48 h), showing a capture rate dependent on the moss species and NPs type. Then, the selected moss species, able to actively capture NPs, appear as a powerful tool capable to purify water from nanostructured materials, and then, to reduce the toxicity associated to the ingestion of contaminated drinking water

    Synergistic effect induced by gold nanoparticles with polyphenols shell during thermal therapy: Macrophage inflammatory response and cancer cell death assessment

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    Background: In recent decades, gold nanoparticle (Au NP)-based cancer therapy has been heavily debated. The physico-chemical properties of AuNPs can be exploited in photothermal therapy, making them a powerful tool for selectively killing cancer cells. However, the synthetic side products and capping agents often induce a strong activation of the inflammatory pathways of macrophages, thus limiting their further applications in vivo. Methods: Here, we described a green method to obtain stable polyphenol-capped AuNPs (Au NPs@polyphenols), as polyphenols are known for their anti-inflammatory and anticancer properties. These NPs were used in human macrophages to test key inflammation-related markers, such as NF-κB, TNF-α, and interleukins-6 and 8. The results were compared with similar NPs obtained by a traditional chemical route (without the polyphenol coating), proving the potential of Au NPs@polyphenols to strongly promote the shutdown of inflammation. This was useful in developing them for use as heat-synergized tools in the thermal treatment of two types of cancer cells, namely, breast cancer (MCF-7) and neuroblastoma (SH-SY5Y) cells. The cell viability, calcium release, oxidative stress, HSP-70 expression, mitochondrial, and DNA damage, as well as cytoskeleton alteration, were evaluated. Results: Our results clearly demonstrate that the combined strategy markedly exerts anticancer effects against the tested cancer cell, while neither of the single treatments (only heat or only NPs) induced significant changes. Conclusions: Au NP@polyphenols may be powerful agents in cancer treatment

    Application of a multi-species bio-economic modelling approach to explore fishing traits within eligible cetacean conservation areas in the Northern Ionian Sea (Central Mediterranean Sea)

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    The assessment of the spatial overlap between eligible cetacean conservation areas (CCAs) and fishing grounds could be a strategic element in the implementation of effective conservation measures in the pelagic offshore areas. A multi-species bio-economic modelling approach has been applied to estimate the fishing traits in eligible CCAs in the Northern Ionian Sea (NIS, Central Mediterranean Sea) between 10-800 m of depth, adopting the Spatial MAnagement of demersal Resources for Trawl fisheries model (SMART). Four possible CCAs were defined according to the distribution of cetacean species, their bio-ecological needs, as well as socio-economic needs of human activities, identifying a Blue, Red, Orange and Green CCAs in the NIS. SMART spatial domain was a grid with 500 square cells (15x15 NM). The analysis was conducted for the period 2016-2019, considering the Otter Trawl Bottom (OTB) fleet activities in the study areas through the Vessel Monitoring System. The spatial extension of fishing activities, hourly fishing effort (h), landings (tons) and economic value (euros) for each CCA and the NIS were estimated as yearly median values. Fishing activities were absent in the Blue CCA, where the presence of the submarine canyon head does not offer accessible fishing grounds. The hourly fishing effort in the Green area accounted for about 22% (3443 h) of the total hourly effort of the NIS, while the Orange and Red areas were about 8% (1226 h) and 2% (295 h), respectively. The Green CCA corresponded to about 14% (36 tons) of the total landings in the NIS, whereas the Orange and Red areas represented about 9% (22 tons) and 6% (16 tons), respectively. The Green CCA accounted for about 13% (156 thousand euros) of the total economic value of the NIS, while the Orange and Red areas represented about 6% (69 thousand euros) and 4% (44thousand euros), respectively. Results showed no or negligible negative effects on trawl activities by potential spatial restrictions due to the establishment of CCAs highlighting the importance to consider spatially integrated information during the establishment process of conservation areas for cetacean biodiversity according to the principles of Ecosystem Based Management

    Estimation of contact lens friction coefficient: The need for a protocol

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    Contact lens discomfort (CLD) is a sporadic or frequent condition that affects millions of contact lens users worldwide. The experience of the contact lenses (CLs) wearers is strongly influenced by many factors, among these the physical properties of lens materials. Especially, the friction coefficient (CoF) plays a critical role in the balance between lenses and ocular environment. The aim of our study is to quantify the CoF for different CLs by means of a nano-tribometer. Three experiments were performed following protocols already published in the literature, in order to evaluate the CoF dependance on testing parameters, such as sliding speed, applied normal force and number of sliding cycles. Our results identify a lack in the reproducibility of already published experiments and the necessity to identify a measuring standardized protocol

    Aloe vera silver nanoparticles addition in chitosan films: improvement of physicochemical properties for eco-friendly food packaging material

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    In recent times, the searches for alternative materials to plastic is a popular topic, due to the danger that synthetic materials cause to the environment and humans. Among the promising natural polymers, chitosan (CS) is certainly one of the most suitable since it it is edible, non-toxic and derives from crustacean waste.- However, it is necessary to improve its physical properties to be widely applied in food packaging, whose market is dominated by synthetic plastic. In this work we have synthesized silver nanoparticles (AgNPs) using hot-plate and microwaves-based techniques, using Aloe Vera leaves extracts. The synthetic process follows the principles of green chemistry, since no toxic substance is used to obtain nanomaterials. These NPs, having dimensions <20 nm, were characterized by TEM, zeta potential, UV-vis, FTIR, and then added to CS having low and medium molecular weight to develop thin films after its polymerization. These films were evaluated in terms of swelling ratio, optical properties, thermal stability, wettability, roughness, and friction coefficient, understanding that the physical properties of the films improved after the intercalation of the AgNPs, albeit differences were observed using the two NPs type. Subsequently, the release of silver ions from films using different pH as well as in vitro toxicity tests were carried out to evaluate their applicability. Largely, the excellent properties of new com- posite materials make them promising materials for packaging of different kinds of foods

    Addressing cetacean–fishery interactions to inform a deep-sea ecosystem-based management in the Gulf of Taranto (Northern Ionian Sea, Central Mediterranean Sea)

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    Understanding of cetaceans’ trophic role and the quantification of their impacts on the food web is a critical task, especially when data on their prey are linked to deep-sea ecosystems, which are often exposed to excessive exploitation of fishery resources due to poor management. This aspect represents one of the major issues in marine resource management, and trade-offs are needed to simultaneously support the conservation of cetaceans and their irreplaceable ecological role, together with sustainable fishing yield. In that regard, food web models can represent useful tools to support decision-making processes according to an ecosystem-based management (EBM) approach. This study provides a focus on the feeding activity occurrence and the trophic interactions between odontocetes and the fishery in the marine food web of the Gulf of Taranto (Northern Ionian Sea, Central Mediterranean Sea), by zooming in on cetaceans’ prey of commercial interest. In particular, the quantification of trophic impacts is estimated using a food web mass-balance model that integrates information on the bathymetric displacement of both cetaceans’ prey and fishing activity. The results are discussed from a management perspective to guide future research and knowledge enhancement activities as well as support the implementation of an EBM approach

    Programmed cell death 4 (PDCD4) as a novel prognostic marker for papillary thyroid carcinoma

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    Background: The primary goal of papillary thyroid cancer (PTC) management was to stratify patients at pre- and post-surgical level to identify the small proportion of cases with potentially aggressive disease. Purpose: The aim of our study is to evaluate the possible role of programmed cell death 4 (PDCD4) and BRAF status as prognostic markers in PTC. Patients and methods: We investigate programmed cell death 4 (PDCD4) immunohistochemical expression in 125 consecutive PTCs with median follow-up of 75.3 months (range, 15\u201398 months) to verify the possible correlation between BRAF status and correlate the classical clinicopathological prognostic factors and PTC outcome with PDCD4 expression. To further support the data, miR-21 expression was tested (by quantitative real-time PCR and in situ hybridization) in a different series of 30 cases (15 PTCs BRAFwt and 15 PTCs BRAFV600E). Moreover, we validated our results using TGCA thyroid carcinoma dataset. Results: We found that 59.8% of the patients showed low-grade PDCD4 nuclear expression and low-grade expression correlated with BRAF V600E. Compared with BRAF 15 wild-type tissue samples, a significant miR-21 up-regulation was associated with BRAF V600E mutations. Lowgrade PDCD4 resulted, and was associated with aggressive histological variants, higher cancer size, extra-thyroidal extension, multifocality, lymph-node metastasis and lymph nodal ratio at the diagnosis. Concerning the outcome, the low-grade PDCD4 expression correlated at univariate and multivariate analysis, with lower levels of recurrence-free survival rate (RFS) and with poor outcome. Moreover, there was significant association between BRAF V600E patients with PDCD4 nuclear loss and lower RFS, whilet here was significant association between BRAF wild-type patients with PDCD4 nuclear expression and better outcome. Conclusion: These results showed that PDCD4 could predict PTC outcome and that the sum of PDCD4 and BRAF alterations increases the prognostic power of BRAF mutation alone

    Alpha-enolase (ENO1) controls alpha v/beta 3 integrin expression and regulates pancreatic cancer adhesion, invasion, and metastasis

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    Background: We have previously shown that in pancreatic ductal adenocarcinoma (PDA) cells, the glycolytic enzyme alpha-enolase (ENO1) also acts as a plasminogen receptor and promotes invasion and metastasis formation. Moreover, ENO1 silencing in PDA cells induces oxidative stress, senescence and profoundly modifies PDA cell metabolism. Although anti-ENO1 antibody inhibits PDA cell migration and invasion, little is known about the role of ENO1 in regulating cell-cell and cell-matrix contacts. We therefore investigated the effect of ENO1 silencing on the modulation of cell morphology, adhesion to matrix substrates, cell invasiveness, and metastatic ability. Methods: The membrane and cytoskeleton modifications that occurred in ENO1-silenced (shENO1) PDA cells were investigated by a combination of confocal microscopy and atomic force microscopy (AFM). The effect of ENO1 silencing was then evaluated by phenotypic and functional experiments to identify the role of ENO1 in adhesion, migration, and invasion, as well as in senescence and apoptosis. The experimental results were then validated in a mouse model. Results: We observed a significant increase in the roughness of the cell membrane due to ENO1 silencing, a feature associated with an impaired ability to migrate and invade, along with a significant downregulation of proteins involved in cell-cell and cell-matrix adhesion, including alpha v/beta 3 integrin in shENO1 PDA cells. These changes impaired the ability of shENO1 cells to adhere to Collagen I and IV and Fibronectin and caused an increase in RGD-independent adhesion to vitronectin (VN) via urokinase plasminogen activator receptor (uPAR). Binding of uPAR to VN triggers integrin-mediated signals, which result in ERK1-2 and RAC activation, accumulation of ROS, and senescence. In shENO1 cancer cells, the use of an anti-uPAR antibody caused significant reduction of ROS production and senescence. Overall, a decrease of in vitro and in vivo cell migration and invasion of shENO1 PDA cells was observed. Conclusion: These data demonstrate that ENO1 promotes PDA survival, migration, and metastasis through cooperation with integrins and uPAR
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