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Artificial Seawater (artificial + seawater)
Selected AbstractsThe influence of ovarian fluid on Solea senegalensis sperm motilityJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2010P. Diogo Summary The role of ovarian fluid in fertilization has been neglected, particularly in marine species. The aim of this work was therefore to assess the influence of ovarian fluid (OF) as a potential contributor factor to sperm motility in Solea senegalensis. The specificity of interactions between sperm and ovarian fluid was analyzed using homologous and heterelogous ovarian fluid. Additional tests tried to identify the most useful concentration for improving sperm motility throughout the activation process. Ovarian fluid solutions were diluted in artificial seawater (SW) (v:v) 0 : 100, 25 : 75, 50 : 50, 75 : 25 and 100 : 0 (OF:SW). Pure ovarian fluid solutions (100%) did not promote sperm motility by themselves since they lack the osmolarity needed to trigger sperm motility. With 75% of ovarian fluid the activation solution promoted a deficient activation and the best concentrations used were 25 and 50%. The presence of ovarian fluid affected significantly total motility (TM) and progressive motility (PM) in the last seconds post activation. Progressive motility was higher at 45 s for homologous 25% OF (20.4%) than control (9.4%). Homologous 25% OF increased significantly TM and PM at 60 s post activation (32.0 and 10.5%, respectively) when compared to control (15.8 and 1.7%, respectively). Sperm velocity showed significant differences in the presence of ovarian fluid since early seconds post activation. Our data revealed an enhancement of sperm motility with ovarian fluid at low concentrations in the activation solution. There seems to be a high degree of specificity of ovarian fluid-sperm interaction since heterologous fluid had a lower performance enhancing sperm motility than homologous fluid. Our results indicated a possible important female contribution to sperm motility enhancement during the fertilization process in S. senegalensis. [source] MODULATION OF VERY-LONG CHAIN (C28) HIGHLY UNSATURATED FATTY ACIDS IN PROROCENTRUM MININUM (DINOPHYCEAE) BY SELENIUMJOURNAL OF PHYCOLOGY, Issue 2000A. Place Recently, very-long-chain (C28) highly unsaturated fatty acids (VLC-HUFA) were identified in seven marine dinoflagellate species (Manour et al., Phytochemistry, 1999, 50: 541,548). In general, the proportion of these fatty acids accounted for less than 2.3% of the total fatty acids in these species. As part of a study investigating the modulation of the hemolytic fatty acid 18:5n3, cultures of Prorocentrum mininum were grown in artificial seawater with varying molarities of sodium selenite (0, 1, 10, and 100 nM). Optimal growth was observed at 1 nM with this media. As expected, the level of 18:5n3 was modulated by the selenium in the culture medium (7.0 ± 0.2, 14.5 ± 0.6, 7.4 ± 0.8, and 3.9 ± 0.8% of total fatty acid, respectively), with the highest percentage found at 1 nM. Unexpectedly the level of VLC-HUFA (28:8n3) increased to 7.3 ± 2.8% at 0 nM sodium selenite, while at all other selenite concentrations the VLC-HUFA was less than 1%. A possible biochemical basis for this finding will be discussed. [source] Effects of isoflurane on measurements of delayed lumininescence in Acetabularia acetabulumLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 1 2005Wen Li Chen Abstract The volatile halogenated methyl ethyl ether, isoflurane, used as an anaesthetic, inhibits actin-based dynamics directly or indirectly in animal cells. In plant cells, most intracellular movements are related to actin pathways. We have used isoflurane in a unicellular alga, Acetabularia acetabulum, to test the dynamics of choloroplast organization. By measuring the delayed luminescence, we found that isoflurane worked efficiently in the unicellular organism and showed dose- and time-course-dependent actin-inhibition patterns. When A. acetabulum was treated with saturated solutions of isoflurane in artificial seawater (defined as 100% isoflurane) for 3 or 6 min, the delayed luminescence (DL) was decreased and was never recovered. In contrast, if treated with 75% diluted isoflurane, the DL was firstly inhibited and then recovered several hours later, and if treated with 50% diluted isoflurane, the change of DL was small. Our work proved that isoflurane can affect actin-related pathways in both animals and plants. Copyright © 2005 John Wiley & Sons, Ltd. [source] Osmoregulation in Six Sympatric Fiddler Crabs (genus Uca) from the Northwestern Gulf of MexicoMARINE ECOLOGY, Issue 4 2002Carl L. Thurman Abstract. As problems in taxonomy and systematic relationships among the Uca species are resolved, a definition of how each fiddler crab species partitions and utilizes habitat resources is needed. To this end, the osmoregulatory capabilities were studied in six species of fiddler crabs from the western Gulf of Mexico. Specimens were placed in 50,ml of artificial seawater ranging in osmolality from 50 to 3450,mOsm (2 to 109,,) for five days. Survivorship was recorded for each species. Uca rapax, U. panacea and U. subcylindrica are hardy from 200 to 3200,mOsm (6 to 101,,). Uca spinicarpa and U. minax survive only below 1400,mOsm (44,,). U. longisignalis is intermediate, with limited survival above 2500,mOsm (79,,). Hemolymph osmolality was determined for crabs surviving the osmotic regimen. Uca panacea, U. subcylindrica and U. rapax are equivalent in their regulation between 50 and 3200,mOsm (2,,,101,,). Uca longisignalis lost its ability to control hemolymph osmolality above 2200,mOsm (69,,). On the other hand, U. spinicarpa and U. minax become less effective hyporegulators in media above 1200 (38,,) and 1500,mOsm (47,,), respectively. Only U. longisignalis appears to exhibit clear differences in osmoregulatory capacity between populations. Population data for U. panacea and laboratory experiments with U. subcylindrica also support the notion of capacitative acclimation in Uca. These physiological capabilities correlate well with the known habitat characteristics for each fiddler crab species in the northwestern Gulf of Mexico. [source] | ||||||||||