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2.
Mar Pollut Bull ; 147: 150-158, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29274953

RESUMO

The intense shipping traffic characterising the Adriatic Sea favours the spread of marine organisms. Yet, a study of 12 Adriatic ports (4 on the western side and 8 on the eastern side of the basin) found that non-indigenous species (NIS) accounted for only 4% of the benthic communities settled on hard substrates. The cirripeds Amphibalanus amphitrite and Balanus trigonus, found in 8 harbours, were the most common invaders followed by Amphibalanus eburneus, the ascidian Styela plicata, and the bivalve Magallana gigas. The highest percentage of NIS was recorded in Venice and Ploce, the harbours with the least rich native communities; the lowest percentage was retrieved in Trieste, Koper, Pula, and Rijeka, the harbours hosting the highest species diversity. In contrast, the ports of Bari and Ancona showed both high NIS percentages and highly diversified communities.


Assuntos
Organismos Aquáticos , Espécies Introduzidas , Invertebrados , Navios , Animais , Monitoramento Biológico , Mar Mediterrâneo , Poríferos , Thoracica , Instalações de Transporte , Urocordados
3.
Mar Pollut Bull ; 147: 229-236, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29336825

RESUMO

Marine bioinvasions and other rapid biodiversity changes require today integrating existing monitoring tools with other complementary detection strategies to provide a more efficient management. Here we explored the efficacy of fishermen observations and traditional port surveys to effectively track the occurrence of both indigenous and non-indigenous megafauna in the Adriatic Sea. This consisted mainly of mobile taxa such as fishes, crustaceans and molluscs. Port surveys using traps and nets within 10 major Adriatic harbours, were compared with the information obtained from 153 interviews with local fishermen. Information gathered by traps and nets varied significantly and generally resulted of limited efficacy in exotic species detection. Interviews allowed tracking the occurrence of new species through time and space, providing complementary knowledge at the low cost. This combined approach improves our capability of being informed on the arrival of species of different origin, providing a more rational, improved basis for environmental management and decision making.


Assuntos
Monitoramento Biológico/métodos , Peixes , Espécies Introduzidas , Invertebrados , Animais , Biodiversidade , Croácia , Pesqueiros , Itália , Conhecimento , Eslovênia , Inquéritos e Questionários
4.
Sci Rep ; 7(1): 16781, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29196667

RESUMO

This work aims to provide deeper knowledge on reproductive biology of P. kerathurus in a multidisciplinary way. Upon 789 examined females, 285 were found inseminated. The logistic equation enabled to estimate the size at first maturity at 30.7 mm CL for female. The Gono-Somatic Index (GSI) showed a pronounced seasonality, ranged from 0.80 ± 0.34 to 11.24 ± 5.72. Histological analysis highlighted five stages of ovarian development. Gonadal fatty acids analysis performed with gas chromatograph evidenced a pronounced seasonal variation; total lipids varied from 1.7% dry weight (dw) in Winter, to 7.2% dw in Summer. For the first time, a chemometric approach (Principal Component Analysis) was applied to relate GSI with total lipid content and fatty acid composition of gonads. The first two components (PC1 and PC2) showed that seasonality explained about 84% of the variability of all data set. In particular, in the period February-May, lipids were characterized by high PUFAs content, that were probably utilized during embryogenesis as energy source and as constituent of the cell membranes. During the summer season, gonads accumulated saturated FAs, that will be used during embryogenesis and early larval stages, while in the cold season total lipids decreased drastically and the gonad reached a quiescent state.


Assuntos
Ácidos Graxos Insaturados/análise , Ovário/crescimento & desenvolvimento , Penaeidae/fisiologia , Animais , Cromatografia Gasosa , Feminino , Ovário/química , Penaeidae/química , Análise de Componente Principal , Reprodução , Estações do Ano
5.
G Ital Med Lav Ergon ; 29(3 Suppl): 498-500, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-18409796

RESUMO

The implementation of the European Directive No 391/89, among the other news, introduced the obligation for the occupational physician to actively participate to the assessment of risks. The reduction of the incidence of "historical" professional pathologies and the arising of work-related disease is making the role of the occupational physician, in the survey and risk assessment, ever more important, especially in consideration of the physiological and biomechanical peculiar competences required. In addition, a correct risk assessment allows to optimise the valorisation of human resources. The occupational physician, in other terms, can not only protect the health of workers, but "save" jobs too. The survey carried out in a logistic unit of a large-scale distributors group, documented herein, can give evidence of that.


Assuntos
Indústrias , Doenças Profissionais/prevenção & controle , Saúde Ocupacional , Humanos , Recursos Humanos
6.
J Hepatol ; 30(5): 868-75, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10365814

RESUMO

BACKGROUND/AIMS: Oxidative stress is associated with liver fibrosis in vivo and with hepatic stellate cell (HSC) activation in vitro, but the intracellular mechanisms mediating these effects are mostly unknown. The Na+/H+ exchanger plays a key role in regulating the cell cycle, and is involved in HSC proliferation. Its role in different HSC features, such as collagen accumulation, is still unknown. We thus evaluated if the Na+/H+ exchanger modulates the fibrogenic effect of oxidative stress in rat HSC. METHODS: HSC were incubated with 0.1 mM ferric nitrilotriacetate complex (FeNTA). Intracellular hydroperoxides and malonildialdehyde (MDA) levels in the culture media were measured by the dichlorofluorescein and TBARS method, respectively. Intracellular pH and Na+/H+ exchanger activity were measured using the fluorescent dye BCECF. Cell proliferation was measured by immunohistochemistry for bromodeoxyuridine incorporation. Collagen type I accumulation in the culture media was measured by ELISA. RESULTS: HSC incubation with FeNTA resulted in a significant production of intracellular hydroperoxides and MDA, associated with increased Na+/H+ exchange activity and baseline intracellular pH (pHi). Exposure of HSC to FeNTA significantly enhanced the number of proliferating HSC and collagen type I levels in the culture medium. All these effects were reversed by the antioxidant resveratrol and by the Na+/H+ exchanger inhibitor amiloride. CONCLUSIONS: This study indicates that the Na+/H+ exchanger might represent a common mediator of the different effects induced by oxidative stress on HSC. The reduction in cell proliferation and collagen synthesis induced by amiloride could represent a new therapeutic challenge in liver fibrosis.


Assuntos
Fígado/fisiologia , Estresse Oxidativo/fisiologia , Trocadores de Sódio-Hidrogênio/metabolismo , Animais , Antioxidantes/farmacologia , Carcinógenos/farmacologia , Ciclo Celular , Divisão Celular , Células Cultivadas , Colágeno/metabolismo , Meios de Cultura , Compostos Férricos/farmacologia , Fluoresceínas , Corantes Fluorescentes , Cinética , Fígado/citologia , Fígado/patologia , Cirrose Hepática Experimental/patologia , Cirrose Hepática Experimental/fisiopatologia , Cirrose Hepática Experimental/prevenção & controle , Malondialdeído/metabolismo , Ácido Nitrilotriacético/análogos & derivados , Ácido Nitrilotriacético/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Resveratrol , Estilbenos/farmacologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise
7.
Gastroenterology ; 116(5): 1155-66, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10220508

RESUMO

BACKGROUND & AIMS: The Na+/H+ exchanger is the main intracellular pH regulator in hepatic stellate cells (HSCs), and its activity is increased by platelet-derived growth factor (PDGF). Amiloride, an Na+/H+ exchange inhibitor, reduces PDGF-induced HSC proliferation, suggesting that the Na+/H+ exchanger plays a role in regulating HSC proliferative response. The aim of this study was to characterize the intracellular pathways mediating activation of the Na+/H+ exchanger by PDGF in HSCs. METHODS: The activity of the Na+/H+ exchanger and HSC proliferation rate were evaluated under control condition and after incubation with PDGF in the absence or presence of specific inhibitors of the main intracellular pathways of signal transduction. Na+/H+ exchange protein expression was evaluated by means of Western blot. RESULTS: PDGF induced a significant increase in the activity of the Na+/H+ exchanger without modifying protein expression. Inhibition of the calcium/calmodulin- and protein kinase C-dependent pathways resulted in a significant inhibition of both Na+/H+ exchange activity and of PDGF-induced HSC proliferation. The involvement of the two pathways was confirmed by showing that incubation of HSCs with both phorbol-12-myristate-13-acetate, a potent protein kinase C activator, and thapsigargin, which increases intracellular calcium levels, significantly increased both the Na+/H+ exchanger activity and HSC proliferation rate. Inhibition of the protein kinase A pathway did not modify either PDGF-induced Na+/H+ exchange activation or PDGF-induced HSC proliferation. On the contrary, inhibition of the mitogen-activated protein kinase- and of phosphatidylinositol 3-kinase-dependent pathways significantly reduced PDGF-induced HSC proliferation without affecting the activity of the Na+/H+ exchanger. CONCLUSIONS: Activation of the Na+/H+ exchanger by PDGF in HSCs is mediated by calcium/calmodulin- and protein kinase C-dependent pathways. PDGF-induced HSC proliferation is mediated by Na+/H+ exchange-dependent and -independent pathways.


Assuntos
Líquido Intracelular/metabolismo , Fígado/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Trocadores de Sódio-Hidrogênio/metabolismo , Animais , Western Blotting , Cálcio/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Calmodulina/antagonistas & inibidores , Calmodulina/metabolismo , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Fígado/citologia , Fígado/efeitos dos fármacos , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Tapsigargina/farmacologia
8.
Biotechnol Bioeng ; 27(8): 1115-21, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18553792

RESUMO

Aspartate glucan, glycine glucan, and serine glucan obtained by reductive amination of oxalacetic acid, glyoxylic acid, and beta-hydroxypyruvic acid, respectively, with polyglucosamine were tested as chromatographic chelating media. Crosslinked glycine glucan exhibited high capacities for cobalt and copper, even in acidic solutions (pH 2.9). Breakthrough points for 10 mg/L solutions through 6.0 x 0.6 cm columns containing 200 mg of polymer were at 1.8 L for both ions; for 1 mg/L solutions, they were at 4.0 and 12.0 L for cobalt and copper, respectively. Crosslinked glycine glucan could remove microgram amounts of cobalt and copper from fluoride and chloride brines. Cobalt and copper could be separated by elution with 0.25M sulfuric acid.

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