69 research outputs found

    Ash leachates from some recent eruptions of Mount Etna (Italy) and Popocatépetl (Mexico) volcanoes and their impact on amphibian living freshwater organisms

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    Leaching experiments were carried out on fresh ash samples from Popocatépetl 2012, Etna 2011, and Etna 2012 eruptions, in order to investigate the release of compounds in both double-deionized and lake (Lake Ohrid, FYR of Macedonia) waters. The experiments were carried out using different grain sizes and variable stirring times (from 30 min to 7 days). Results were discussed in the light of changing pH and release of compounds for the different leachates. In particular, Etna samples induced alkalinization, and Popocatépetl samples induced acidification of the corresponding leachates. The release of different elements does not show correlation with the stirring time, with the measured maximum concentrations reached in the first hours of washing. General inverse correlation with grain size was observed only for Na+, K+, Cl-, Ca2+, Mg2+, SO2-4 , and Mn2+, while the other analysed elements show a complex, scattering relationship with grain size. Geochemical modelling highlights leachates' saturation only for F and Si, with Popocatépetl samples sometimes showing saturation in Fe. The analysed leachates are classified as undrinkable for humans on the basis of European laws, due to excess in F-, Mn2+, Fe, and SO2-4 (the latter only for Popocatépetl samples). Finally, the Etna 2012 and Popocatépetl leachates were used for toxicity experiments on living biota (Xenopus laevis). They are mildly toxic, and no significant differences exist between the toxic profiles of the two leachates. In particular, no significant embryo mortality was observed; while even at high dilutions, the leachates produced more than 20% of malformed larvae

    Role of air pollutants mediated oxidative stress in respiratory diseases

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    Airborne particulate (PM) components from fossil fuel combustion can induce oxidative stress initiated by reactive oxygen species (ROS) that are strongly correlated with airway inflammation and asthma. A valid biomarker of airway inflammation is fractionated exhaled nitric oxide (FENO). The oxidative potential of PM2.5 can be evaluated with the dithiothreitol (DTT) dosage, which represents both ROS chemically produced and intracellular ROS of macrophages. This correlates with quality indicators of the internal environment and ventilation strategies such as dilution and removal of airborne contaminants

    Milano summer particulate matter (PM10) triggers lung inflammation and extra pulmonary adverse events in mice

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    Recent studies have suggested a link between particulate matter (PM) exposure and increased mortality and morbidity associated with pulmonary and cardiovascular diseases; accumulating evidences point to a new role for air pollution in CNS diseases. The purpose of our study is to investigate PM10sum effects on lungs and extra pulmonary tissues. Milano PM10sum has been intratracheally instilled into BALB/c mice. Broncho Alveolar Lavage fluid, lung parenchyma, heart and brain were screened for markers of inflammation (cell counts, cytokines, ET-1, HO-1, MPO, iNOS), cytotoxicity (LDH, ALP, Hsp70, Caspase8-p18, Caspase3-p17) for a putative pro-carcinogenic marker (Cyp1B1) and for TLR4 pathway activation. Brain was also investigated for CD68, TNF-\u3b1, GFAP. In blood, cell counts were performed while plasma was screened for endothelial activation (sP-selectin, ET-1) and for inflammation markers (TNF-\u3b1, MIP-2, IL-1\u3b2, MPO). Genes up-regulation (HMOX1, Cyp1B1, IL-1\u3b2, MIP-2, MPO) and miR-21 have been investigated in lungs and blood. Inflammation in the respiratory tract of PM10sum-treated mice has been confirmed in BALf and lung parenchyma by increased PMNs percentage, increased ET-1, MPO and cytokines levels. A systemic spreading of lung inflammation in PM10sum-treated mice has been related to the increased blood total cell count and neutrophils percentage, as well as to increased blood MPO. The blood-endothelium interface activation has been confirmed by significant increases of plasma ET-1 and sP-selectin. Furthermore PM10sum induced heart endothelial activation and PAHs metabolism, proved by increased ET-1 and Cyp1B1 levels. Moreover, PM10sum causes an increase in brain HO-1 and ET-1. These results state the translocation of inflammation mediators, ultrafine particles, LPS, metals associated to PM10sum, from lungs to bloodstream, thus triggering a systemic reaction, mainly involving heart and brain. Our results provided additional insight into the toxicity of PM10sum and could facilitate shedding light on mechanisms underlying the development of urban air pollution related diseases

    Do nanoparticle physico-chemical properties and developmental exposure window influence nano ZnO embryotoxicity in Xenopus laevis?

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    The growing global production of zinc oxide nanoparticles (ZnONPs) suggests a realistic increase in the environmental exposure to such a nanomaterial, making the knowledge of its biological reactivity and its safe-by-design synthesis mandatory. In this study, the embryotoxicity of ZnONPs (1\u2013100 mg/L) specifically synthesized for industrial purposes with different sizes, shapes (round, rod) and surface coatings (PEG, PVP) was tested using the frog embryo teratogenesis assay-Xenopus (FETAX) to identify potential target tissues and the most sensitive developmental stages. The ZnONPs did not cause embryolethality, but induced a high incidence of malformations, in particular misfolded gut and abdominal edema. Smaller, round NPs were more effective than the bigger, rod ones, and PEGylation determined a reduction in embryotoxicity. Ingestion appeared to be the most relevant exposure route. Only the embryos exposed from the stomodeum opening showed anatomical and histological lesions to the intestine, mainly referable to a swelling of paracellular spaces among enterocytes. In conclusion, ZnONPs differing in shape and surface coating displayed similar toxicity in X. laevis embryos and shared the same target organ. Nevertheless, we cannot exclude that the physico-chemical characteristics may influence the severity of such effects. Further research efforts are mandatory to ensure the synthesis of safer nano-ZnO-containing products

    Consensus statement of the Italian society of pediatric allergy and immunology for the pragmatic management of children and adolescents with allergic or immunological diseases during the COVID-19 pandemic

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    The COVID-19 pandemic has surprised the entire population. The world has had to face an unprecedented pandemic. Only, Spanish flu had similar disastrous consequences. As a result, drastic measures (lockdown) have been adopted worldwide. Healthcare service has been overwhelmed by the extraordinary influx of patients, often requiring high intensity of care. Mortality has been associated with severe comorbidities, including chronic diseases. Patients with frailty were, therefore, the victim of the SARS-COV-2 infection. Allergy and asthma are the most prevalent chronic disorders in children and adolescents, so they need careful attention and, if necessary, an adaptation of their regular treatment plans. Fortunately, at present, young people are less suffering from COVID-19, both as incidence and severity. However, any age, including infancy, could be affected by the pandemic. Based on this background, the Italian Society of Pediatric Allergy and Immunology has felt it necessary to provide a Consensus Statement. This expert panel consensus document offers a rationale to help guide decision-making in the management of children and adolescents with allergic or immunologic diseases

    DDT polluted meltwater affects reproduction in the mussel Dreissena polymorpha

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    The zebra mussel Dreissena polymorpha was used to follow the recently reported DDT pollution of Lake Iseo (N. Italy). Histopathological analyses were performed on mussels sampled from March 2005 to April 2006, when high DDT levels were found, and results were compared to those from mussels sampled in 2001/2002, before the pollution event. During the 2005/2006 reproductive season, the first male gamete release happened one month later than the onset of spawning in females who showed a high number of specimens with degenerating oocytes, despite a regular pattern of gametogenesis. These results indicated a disrupting action of DDT on the mechanisms involved in sperm release, and a disturbance in the gametogenic phases of the ovary. Pathological pictures in the digestive gland of many mussels from both 2001/2002 and 2005/2006 have also been observed, but DDT pollution is unable to explain the presence of pathological fields in mussels during 2001/2002, for which a previously reported contamination seems to be the main cause. A possible role of DDT in skewing the sex ratio towards a predominance of females was also discussed, considering the high number of females sampled in 2005/2006. \ua9 2009 Elsevier Ltd. All rights reserved

    Sexual maturity in young Dreissena polymorpha from Lake Como (N. Italy)

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    The reproductive biology of the zebra mussel Dreissena polymorpha was studied during 1999 in a natural population living in Lake Como (N. Italy), with particular reference to the differences in behavior between young and adult mussels. Histological analysis of gonads was used to study the gametogenic cycles and to evaluate when the young reached sexual maturity. Signs of active gametogenesis were detected in greater than or equal to4 mm shell length mussels. Mature gametes and the first spawning events were observed in greater than or equal to5 mm males and in greater than or equal to6 females. The gonad feature of greater than or equal to7 mm mussels was similar to that of the adults. Size frequency distributions revealed that the new generation (0(+)) first spawned in the year following birth, but only after winter. The length of larval time seemed to vary greatly depending on the spawning period, in addition to the environmental conditions. The first settled mussels greater than or equal to500 mum in shell length were observed 3-4 months after the first depositions. Water temperature seemed to be the most important factor which regulated sexual phenomena of both young and adult mussels. Its role in the onset of the spawning events was confirmed, but it is important to point out that temperature is not enough to trigger reproduction since gamete release is impossible without sufficient energy, especially for young mussels

    Zebra mussels in Italy : where do they come from?

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    The zebra mussel Dreissena polymorpha is widely present in Italy, but Italian populations of this bivalve have never been genetically characterized. The mitochondrial Cytochrome Oxidase subunit I gene fragments have been used to determine the genetic structures of 3 populations from Lake Garda (n = 30), the first Italian basin colonized by this species, as well as 2 populations from Lake Constance, Germany (n = 14). A Neighbor-Joining tree and a Maximum Likelihood analysis were performed with 4 new Italian (LG1-LG4) and 3 German (LC1-LC3) haplotypes, also considering all the available Dreissena sequences from GenBank in order to estimate phylogeographic relationships. Almost all Italian haplotypes clustered with German and mid-European samples providing evidences of a mixed origin for Italian mussels. We speculate about Lake Garda colonization, for which the hypothesized "German origin" has been partially confirmed as well as the necessity of more efficient control strategies at least to minimize new colonizations

    Reproductive behavior of the freshwater mussel Dreissena polymorpha in Italy: a comparison between two populations

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    The gametogenic cycle of Dreissena polymorpha is described for two populations living in Lake Come and the Adda River in Northern Italy. Reproduction was monitored by histological examinations of gonads and by morphometric changes in oocyte nuclei from February 1998 to January 1999. Gonadal development commenced overwinter. Gamete deposition started in spring when the water temperature reached 13 degreesC. By May, the reproductive season had commenced but while in Lake Come it finished in August, in the Adda River depositions were observed until the end of October. The course of the Maturity Index and mainly the oocyte nuclei diameter analysis suggested the possibility of two main reproductive events in the lake zebra mussel population. In contrast, more continuous spawning was observed in the river mussels. In both sites, frequency distributions of nucleus size showed maturation of at least two gamete cohorts which supported successive depositions. The gonadal resting stage was longer in males than females. Oogenesis started soon after the end of the reproductive period while spermatogenesis commenced only 3 or 4 months later. This is the first study dealing with the Dreissena polymorpha reproductive cycle in the South Alps. Results are discussed and compared with regard to other populations living in the rest of Europe and North America
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