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Simone Bacchiocchi Debora Campacci Melania Siracusa Alessandra Dubbini Francesca Leoni Tamara Tavoloni Stefano Accoroni Stefania Gorbi Maria Elisa Giuliani Arianna Stramenga Arianna Piersanti 《Marine drugs》2021,19(6)
Tetrodotoxins (TTXs), potent neurotoxins, have become an increasing concern in Europe in recent decades, especially because of their presence in mollusks. The European Food Safety Authority published a Scientific Opinion setting a recommended threshold for TTX in mollusks of 44 µg equivalent kg−1 and calling all member states to contribute to an effort to gather data in order to produce a more exhaustive risk assessment. The objective of this work was to assess TTX levels in wild and farmed mussels (Mytilus galloprovincialis) harvested in 2018–2019 along the coastal area of the Marche region in the Central Adriatic Sea (Italy). The presence of Vibrio spp. carrying the non-ribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) genes, which are suspected to be involved in TTX biosynthesis, was also investigated. Out of 158 mussel samples analyzed by hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry (HILIC-MS/MS), 11 (7%) contained the toxins at detectable levels (8–26 µg kg−1) and 3 (2%) contained levels above the EFSA safety threshold (61–76 µg kg−1). Contaminated mussels were all harvested from natural beds in spring or summer. Of the 2019 samples, 70% of them contained V. alginolyticus strains with the NRPS and/or PKS genes. None of the strains containing NRPS and/or PKS genes showed detectable levels of TTXs. TTXs in mussels are not yet a threat in the Marche region nor in Europe, but further investigations are surely needed. 相似文献
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Bogdanos DP Gilbert D Bianchi I Leoni S Mitry RR Ma Y Mieli-Vergani G Vergani D 《Journal of Autoimmune Diseases》2004,1(1):4
BACKGROUND: Antibodies to a cytosolic soluble liver antigen (SLA) are specifically detected in patients with autoimmune hepatitis (AIH). The target of anti-SLA has been identified as a ~50 kDa UGA serine tRNA-associated protein complex (tRNP(Ser)Sec), through the screening of cDNA libraries. A recent report questioned the identity of tRNP(Ser)Sec as the real SLA antigen. The latter study identified alpha-enolase as a major anti-SLA target, through proteomic analysis. METHODS: In an attempt to explain the observed discrepancy we have investigated reactivity of SLA positive sera against alpha-enolase and tRNP(Ser)Sec using rat and primate liver homogenate and the recombinant antigens. Thirty-three serum samples, 11 from SLA-positive patients and 22 from SLA negative controls were investigated. SLA antibodies were detected by an inhibition ELISA and confirmed by immunoblot using human liver homogenate. Autoantibody reactivity was further evaluated using preparations of primate and rat liver homogenates. Anti-alpha-enolase antibody reactivity has been tested by immunoblot using recombinant alpha-enolase. An affinity purified goat polyclonal anti-alpha-enolase IgG antibody was used as reference serum sample. Anti-tRNP(Ser)Sec antibody reactivity was detected by ELISA or dot blot using recombinant tRNP(Ser)Sec antigen. RESULTS AND DISCUSSION: The affinity purified IgG antibody directed to human alpha-enolase gave a band of approximately 48 kDa in both human and rat liver homogenates. A high titre anti-tRNP(Ser)Sec antibody serum gave a single band of ~50 kDa in both liver preparations. All but one anti-SLA antibody positive sera reacted with a ~50 kDa but none immunofixed a 48 kDa band. All anti-SLA antibody positive sera reacted strongly with the recombinant full length tRNP(Ser)Sec protein. None of the anti-SLA negative sera reacted with tRNP(Ser)Sec. Anti-SLA positive, and anti-SLA negative sera reacted equally against recombinant alpha-enolase by immunoblot. Pre-incubation of anti-SLA positive sera with tRNP(Ser)Sec completely abolished the 50 kDa band. The findings of the present study indicate that alpha-enolase and tRNP(Ser)Sec are both expressed in primate and rat liver and have a respective MW of 48 and 50 kDa. They also show that anti-tRNP(Ser)Sec - but not anti-alpha-enolase - correlates with anti-SLA antibody reactivity. CONCLUSION: Our findings indicate that tRNP(Ser)Sec is the most likely target of anti-SLA. 相似文献
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Valerio Leoni Carlo Cremisini Alessandra Casuccio Antonio Gullotti 《Pest management science》1991,31(2):209-220
Multi-residue analyses of pesticides and related compounds generally require clean-up procedures for the elimination of interfering substances. An analytical procedure for use in the recovery and determination of pesticides and other pollutants in water samples is described, in which the purification of the extracts is improved by the separation of pesticides into four groups. The separation of pesticides by silica-gel microcolumn chromatography is explained in detail. 相似文献
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F Berlinguer GG Leoni S Succu F Mossa M Galioto M Madeddu S Naitana 《Reproduction in domestic animals》2007,42(2):202-207
The influence of trehalose on European mouflon spermatozoa cryopreservation during the non-breeding season was tested. Semen was frozen in two different extenders: (a) recommended Tris-based ram extender (CTR); (b) CTR extender supplemented with trehalose 0.147 mm (TRH). Sperm viability and acrosome integrity were assessed using propidium iodide and fluorescein isothiocynate labelled Pisum Sativum agglutinin. Trehalose significantly enhanced sperm viability after thawing compared with CTR extender (62.7% vs 51.8%; p < 0.05), whereas no differences were observed on acrosome integrity (42.9% vs 42.1%). Trehalose influence was also evidenced in the in vitro fertility test performed with sheep oocytes matured in vitro. Both fertilization rates (60.9% TRH vs 43.6% CTR; p < 0.05) and cleavage rates (58% TRH vs 39.8% CTR; p < 0.001) were higher for trehalose frozen semen compared with control extender frozen semen. A higher percentage of zygotes resulting from fertilization with trehalose cryopreserved semen presented the first cleavage earlier if compared with the group fertilized with control semen (48.7% vs 31.5%, respectively; p < 0.01). This result was confirmed by embryo kinetic development. Fertilization with trehalose cryopreserved semen leaded to an higher percentage of blastocysts (40.2% vs 27.8% CTR; p < 0.05), and enhanced in particular the number of blastocysts that developed on the day 6th of culture (28.6% vs 17% CTR; p < 0.05). Our data demonstrated that, during mouflon non-breeding season, trehalose extender enhances spermatozoa viability and its in vitro fertilizing capacity, allowing the production of an higher number of blastocysts. 相似文献
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The aim of this study was to evaluate the effect of gonadotropin treatment on the in vitro maturation, blastocyst production, and developmental potential to term of oocytes collected from Sardinian neonatal and prepubertal ewes at 4 to 6 wk of age. Cumulus-oocyte complexes were recovered at 24 h after withdrawal of a 1/6th size progestagenated pessary from the donors, of which each received 120 IU FSH/LH and 400 IU PMSG in a single dose 36 h before sponge removal. Treated donors produced a greater (P<.01) number of oocytes per animal (86.2 +/-7.9) compared with slaughterhouse (untreated) prepubertal ewes (55.5+/-6.1) of the same age or with treated neonatal ewes (6.1+/-0.7) 10 d old. During oocyte maturation, there were no differences in the percentage of germinal vesicle break-down (78.08 vs. 74.24), metaphase I (89.13 vs. 87.18), and metaphase II (77.91 vs. 76.38) when evaluated after 8, 14, and 24 h of maturation, respectively, between oocytes from treated and slaughterhouse (untreated) prepubertal ewes. The embryo cleavage (71.1 vs. 73.7) and blastocyst rates (22.2 vs. 19.8) were similar in the treated and the untreated prepubertal ewes after transfer of in vitro matured oocytes into ligated oviducts of temporary recipients. The in vitro viability rates of vitrified blastocysts (81.2 vs. 76.9) and the in vivo survival rates (46.1 vs. 50.0) of embryos derived from in vitro matured and in vivo fertilized oocytes showed no difference. The data suggest that gonadotropin treatment increases oocyte production per animal but has no effect on oocyte quality because embryo production and lambing rates of blastocysts derived from in vitro matured oocytes were not markedly different from those derived from untreated prepubertal ewes of the same age. 相似文献
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Vanina Leoni Alexandre Vela Vanina Pasqualini Christine Pergent‐Martini Gérard Pergent 《水产资源保护:海洋与淡水生态系统》2008,18(2):202-220
- 1. Excessive nutrient discharge, linked to human activities, is one of the main causes of the decline of seagrass meadows since it modifies two essential parameters controlling their primary production: the nutrient concentrations (especially nitrogen and phosphorus) and the irradiance.
- 2. To investigate the behaviour of seagrass under varied conditions of light and/or nutrient concentrations, it is necessary to experimentally manipulate nutrient enrichment and light, either in situ or in artificial ecosystems. The available experimental information concerning the influences of light reduction and nutrient enrichments (N and P) on seagrass meadows are summarized.
- 3. The protocols for experimentally reducing light vary considerably but all light reduction experiments show a decrease in seagrass vitality and physiological changes (e.g. promotes an increase in chlorophyll and tissue nitrogen), depending on the species‐specific tolerance (light optima).
- 4. A wide range of protocols for experimentally increasing nutrient levels have been applied, including varying the nutrient species quantities and ratios, as well as the sources and frequency of additions. Responses to N and/or P enrichment range from stimulation to direct or indirect inhibition, varying depending upon the species, the protocol implemented, the nutrient source (water column versus sediments), and other environmental conditions (e.g. interactions with factors such as temperature, grazing and light).
- 5. Both light reduction and nutrient enrichment, can cause seagrass decline, through similar internal mechanisms, promoting an imbalance of internal nutrient supply ratios. Similar physiological responses can thus be observed (e.g. increase of N, P and chlorophyll contents of leaves).
- 6. This study shows the close link between the physiology and morphology of seagrasses, with regard to environmental modifications. It also highlights their ability to provide information on environmental conditions by means of their responses.
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