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Marta Monari Gian Paolo Serrazanetti Jurgen Foschi Valerio Matozzo Maria Gabriella Marin Otello Cattani 《Marine Biology》2007,151(3):1059-1068
The effects of different salinity levels (28, 34 and 40‰) on functional responses of Chamelea gallina haemocytes were evaluated in a two part study dealing with modulations of immune parameters. This part (Part II) of the study
was focused on the superoxide dismutase (SODs) activity and expression in haemocyte lysate and cell-free haemolymph. Results
of this study established that the exposure of C. gallina specimens at 40‰ salinity provoked a decrease in Mn-SOD and Cu/Zn-SOD activities in haemocyte lysate suggesting a declining
superoxide anion generation at the highest salinity tested. Expression of MnSOD was coherent with activity values, while Cu/ZnSOD
showed two immunoreactive bands. The former corresponds to the cytosolic Cu/Zn-SOD (16 kDa) was not coherent with the enzyme
activity and the second (28–30 kDa) probably attributed to EC-SOD. In cell-free haemolymph, Mn-SOD activity decrease and Cu/Zn-SOD
activity increase at 40‰ were observed, likely due to EC-SOD contribution, strongly induced at the same salinity. After EC-SOD
detection with two different antibody, we postulate that the EC-SOD like-protein band (29 kDa) may be constitute partly by
EC-SOD and probably by Cu/Zn-SOD dimeric form not completely dissociated under reducing condition or a Cu/Zn-SOD degenerated
but still recognized by antibody. The cell-free haemolymph increase of EC-SOD at high salinity values plays an important role
in immune defence of C. gallina. According to the conclusion of Part I of this study, our data confirmed the destabilizing effect of 40‰ salinity on haemocyte
functionality, while to 28‰ exposure, data don’t confirm its stressful action as instead stated by results of Part I. Further
studies are necessary to clear up this discrepancy. 相似文献
2.
Valerio Matozzo Marta Monari Jurgen Foschi Gian Paolo Serrazanetti Otello Cattani Maria Gabriella Marin 《Marine Biology》2007,151(3):1051-1058
In the present study, the effects of differing salinities on some important functional responses of haemocytes from the clam,
Chamelea gallina, were investigated. The animals were kept for 7 days at 28‰ (hyposalinity), 34‰ (control) and 40‰ salinity (hypersalinity),
and total haemocyte count (THC), haemocyte volume, phagocytosis, lysozyme-like activity (in both haemocyte lysate and cell-free
haemolymph) were measured. The survival-in-air test was also performed. Clams kept at 28‰ showed significantly increased THC
with respect to animals kept at 34 and 40‰. The analysis of haemocyte size frequency distribution highlighted that in clams
kept at 28‰ the haemocyte fraction of about 5 μm in diameter and 50–100 femtolitre in volume increased markedly. Conversely,
in animals kept at 40‰ an increase was observed in the haemocyte fraction having about 8–10 μm diameter and 400–500 femtolitre
volume. Higher phagocytic activity was recorded in haemocytes from control clams, with respect to that of clams kept at 28
and 34‰. Lysozyme-like activity in haemocyte lysate was shown to increase significantly in animals kept at 28‰ with respect
to that of clams kept at 40‰, whereas enzyme activity in cell-free haemolymph from clams kept at 34‰ was significantly higher
with respect to that of clams maintained at 40‰. A relationship between phagocytosis and lysozyme secretion is suggested.
The resistance to air exposure of clams kept at 28 and 40‰ was shown to decrease significantly; LT50 values fell from 7 days in clams kept at 34‰ to 4 and 5 days in those kept at 28 and 40‰, respectively. Results demonstrated
that salinity values far from 34‰ affects the functional responses of haemocytes and reduce the resistance of clams to exposure
to air. 相似文献
3.
F. Pranovi S. Raicevich G. Franceschini P. Torricelli O. Giovanardi 《Marine Biology》2001,139(5):863-875
This paper describes the catch composition in the rapido trawl fishery and the direct effects on non-target species. All data were collected on commercial fishing vessels so as to reflect commercial rapido-trawling practice. The effects on non-target species were measured using two different damage scales (three- and seven-level scales) depending on the morphology of the taxa. Damage assessment was performed taking into account the whole fishing process by collecting individuals that passed through the cod-end, individuals that were retained in the cod-end and dropped onto the deck and individuals that were collected at the end of the sorting operation just before their return to the sea. Due to differences in the habitat and spatial distribution of target species, discard/commercial ratio was very different among the three different target species fisheries: 1:6 in the queen scallop (Aequipecten opercularis) fishery, 2:1 in the flatfish (Solea spp., Platichthys flesus, Psetta maximus and Scophthalmus rhombus) fishery and 9:1 in the scallop (Pecten jacobaeus) fishery. Damage sustained by non-target species was species-specific and related to the morphology of different organisms. The sorting operation produced similar levels of injury to those of the gear itself: all discarded animals showed higher levels of damage after the sorting than before. Damage to animals that had passed through the cod-end followed the same pattern, and these data could give an estimate of the "unobserved mortality". Our observations indicated a higher impact on non-target species caused by the queen scallop fishery than that caused by the flatfish fishery. This could be due to the total amount of hard-shelled species (in the queen scallop fishery, A. opercularis accounted for 87% of the total catch biomass) in any given haul, since shells macerated the catch during towing. Discarded animals from the queen scallop fishery showed higher levels of damage than those collected in the flatfish fishery. The rapido trawl fishery seemed to exert a strong selective pressure on the macrobenthic community, being able to modify the epibenthic fauna structure which, in heavily exploited fishing grounds, was dominated by bivalves, gastropods, crabs, starfish and brittlestars. 相似文献
4.
Mechanical clam dredging in Venice lagoon: ecosystem effects evaluated with a trophic mass-balance model 总被引:1,自引:0,他引:1
F.?PranoviEmail author S.?Libralato S.?Raicevich A.?Granzotto R.?Pastres O.?Giovanardi 《Marine Biology》2003,143(2):393-403
Harvesting of the invasive Manila clam, Tapes philippinarum, is the main exploitative activity in the Venice lagoon, but the mechanical dredges used in this free-access regime produce a considerable disturbance of the lagoon ecosystem. An ecosystem approach to study the complex effects of clam harvesting was implemented using a trophic mass-balance model. The trophic relations in the ecosystem were quantified with a mixed trophic impact analysis and further evaluated by considering different explanations for the " Tapes paradox", which consists of the apparent population enhancement of Manila clams by dredging and the apparent nutritional advantages that this species receives from re-suspended organic matter. The key-role played by this introduced species is highlighted by a network analysis that indicates a "wasp-waist control" of the system by Manila clams. The model constructed to characterise the present state of the Venice lagoon ecosystem is compared with models produced for a reconstructed past lagoon and a projected future lagoon. The future model was obtained by simulating the elimination of clam dredging in 10 years. The three different models were compared using thermodynamic and informational indices. Simulating the elimination of clam dredging produced a 33% increase in artisanal fishery catches, carried out by means of static gears, even with no change in fishing effort. These simulations also forecast an increase in the mean trophic level of the artisanal fishery catches as a positive effect of eliminating mechanical clam harvesting. 相似文献
5.
Luisa Barbieri Roberto Giovanardi Isabella Lancellotti Marco Michelazzi 《Environmental Chemistry Letters》2010,8(2):171-178
A new method for the recovery of precious metals, in particular gold, from electronic waste is proposed. This work focused
on the research of an easily renewable etching agent, in order to make an environmentally friendly process possible. Two well
known hydrometallurgical etching agents, FeCl3 and CuCl2, were evaluated in terms of efficiency and kinetics, testing solutions with different concentration of etchant and hydrochloric
acid. The recovery of spent etching solutions was evaluated: promising results were found in the case of CuCl2, which can be completely restored by oxidation of the cuprous chloride formed during the etching using atmospheric oxygen. 相似文献
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