Lipid and fatty acid composition, and persistent organic pollutant levels in tissues of migrating Atlantic bluefin tuna (Thunnus thynnus, L.) broodstock.

Lipid class, fatty acid and POP levels were measured in migrating Atlantic bluefin tuna (ABT) tissues caught off the Barbate coast, Spain. Tissue lipids were largely characterized by triacylglycerol, reflecting large energy reserves accumulated prior to reproductive migration. Fatty acid compositions of muscle, liver and adipose exhibited similar profiles, whereas gonads showed a higher affinity for docosahexaenoic acid.

Development of a light microscopy stain for the sclerites of Gyrodactylus von Nordmann, 1832 (Monogenea) and related genera.

Recent developments in semi-automated identification techniques and the increasing ability to rapidly access digital images and taxonomic descriptions offer to increase the range of individuals capable of performing taxonomic identifications. The present study details methodological approaches undertaken in developing a dedicated stain for the visualisation of monogenean haptoral skeletal elements and reproductive sclerites. The histochemical protocols centre around the use of fluorescent dyes and standard light and laser scanning confocal microscopy to support studies of the functional morphology of these hard structures in small, relatively uncompressed specimens, making these structures more amenable to semi-automated analysis and identification techniques.

Molecular cloning and characterisation of a novel P-glycoprotein in the salmon louse Lepeophtheirus salmonis.

The salmon louse, Lepeophtheirus salmonis, is a crustacean ectoparasite of salmonid fish. At present, sea louse control on salmon farms relies heavily upon chemical treatments. Drug efflux transport, mediated by ABC transporters such as P-glycoprotein (Pgp), represents a major mechanism for drug resistance in parasites.

Effects of transient receptor potential (TRP) channel agonists and antagonists on slowly adapting type II mechanoreceptors in the rat sinus hair follicle.

The possible functional role of transient receptor potential (TRP) channels was investigated by testing various TRP agonists and antagonists in an isolated rat sinus hair follicle preparation. Extracellular recordings from slowly adapting type II mechanoreceptor units were made. The antagonist capsazepine depressed spontaneous and mechanically evoked activity, with an IC(50) of 82 microM.

Encoding and retrieval in a model of the hippocampal CA1 microcircuit.

It has been proposed that the hippocampal theta rhythm (4-7 Hz) can contribute to memory formation by separating encoding (storage) and retrieval of memories into different functional half-cycles (Hasselmo et al. (2002) Neural Comput 14:793-817). We investigate, via computer simulations, the biophysical mechanisms by which storage and recall of spatio-temporal input patterns are achieved by the CA1 microcircuitry.

Highly unsaturated fatty acid synthesis in Atlantic salmon: characterization of ELOVL5- and ELOVL2-like elongases.

Fish species vary in their capacity to biosynthesize the n-3 long-chain polyunsaturated fatty acids (LC-PUFA), eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids that are crucial to the health of higher vertebrates. The synthesis of LC-PUFA involves enzyme-mediated fatty acyl desaturation and elongation. Previously, a complementary DNA (cDNA) for an elongase, now termed elovl5a, had been cloned from Atlantic salmon.

Group II metabotropic glutamate receptors reduce excitatory but not inhibitory neurotransmission in rat barrel cortex in vivo.

Group II metabotropic (mGlu) receptors are known to play an important role in regulating the release of excitatory transmitter in a number of brain areas. Previous experiments demonstrated that (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD) depressed excitatory transmission in the adult rat barrel cortex. Here we show, using in vivo extracellular single unit recordings and iontophoretic application of drugs, that selective activation of Group II mGlu receptors depresses excitatory but not inhibitory transmission.

Replacement of dietary fish oil with increasing levels of linseed oil: modification of flesh fatty acid compositions in Atlantic salmon (Salmo salar) using a fish oil finishing diet.

Five groups of salmon, of initial mean weight 127 +/- 3 g, were fed increasing levels of dietary linseed oil (LO) in a regression design. The control diet contained capelin oil (FO) only, and the same oil was blended with LO to provide the experimental diets. After an initial period of 40 wk, all groups were switched to a finishing diet containing only FO for a further 24 wk.

The seeds of Lotus japonicus lines transformed with sense, antisense, and sense/antisense galactomannan galactosyltransferase constructs have structurally altered galactomannans in their endosperm cell walls.

Galactomannan biosynthesis in legume seed endosperms involves two Golgi membrane-bound glycosyltransferases, mannan synthase and galactomannan galactosyltransferase (GMGT). GMGT specificity is an important factor regulating the distribution and amount of (1-->6)-alpha-galactose (Gal) substitution of the (1-->4)-beta-linked mannan backbone. The model legume Lotus japonicus is shown now to have endospermic seeds with endosperm cell walls that contain a high-Gal galactomannan (mannose [Man]/Gal = 1.

Pyloric ceca are significant sites of newly synthesized 22:6n-3 in rainbow trout (Oncorhynchus mykiss).

In this pulse-chase study, rainbow trout fed a diet containing deuterated (D5) (17,17,18,18,18)-18:3n-3 ethyl ester accumulated D5-22:6n-3 in pyloric ceca to a greater extent than in liver 2 d post-dose. The ratio of newly synthesized D5-22:6n-3 in ceca to that in liver 2 d after feeding D5-18:3n-3 was 4.7 +/- 1.

The impact of a structured programme of asthma care in general practice.

The impact of a new GP programme of asthma care was examined using: a) a retrospective pre- and post-casenote survey of 400 asthma patients, comparing patients in practices using the health board programme (HBP) and other programmes (OP); and b) a patient satisfaction questionnaire, completed by 532 people on asthma clinic lists in HBP and OP practices. Outcomes assessed were health service use, perceived change in symptoms and asthma self-management. The casenote survey indicated improved health service use by patients in HBP practices, with fewer patient-initiated (p < 0.

Commercial trials using emamectin benzoate to control sea lice Lepeophtheirus salmonis infestations in Atlantic salmon Salmo salar.

Two trials were conducted at commercial salmon farms to evaluate the efficacy of emamectin benzoate (Slice, 0.2% aquaculture pre-mix, Schering-Plough Animal Health) as a treatment for sea lice Lepeophtheirus salmonis (Krøyer) and Caligus elongatus Nordmann infestations in Atlantic salmon Salmo salar L. Trials were carried out in 15 m2 commercial sea pens, at temperatures of 5.

Depletion of alpha-tocopherol and astaxanthin in Atlantic salmon (Salmo salar) affects autoxidative defense and fatty acid metabolism.

Duplicate groups of Atlantic salmon post-smolts were fed four purified diets supplemented with both vitamin E and the carotenoid astaxanthin (Ax) (+E, +Ax), or supplemented with either vitamin E or Ax (-E, +Ax and +E, -Ax) or deficient in both vitamin E and Ax (-E, -Ax) for 22 wk. There were no effects of diet on growth rate, but an extensive lipoid liver degenerative lesion was observed in 15% of fish fed diets deficient in vitamin E. Tissue vitamin E concentrations varied in accordance with dietary vitamin E in liver, muscle, heart, plasma, brain and eye; levels were reduced to approximately 3% in liver but only to 40% in eye of fish fed diets deficient in vitamin E compared with those fed diets supplemented with vitamin E.

Molecular characterisation of a membrane-bound galactosyltransferase of plant cell wall matrix polysaccharide biosynthesis.

Galactomannan biosynthesis in vitro is catalysed by membrane preparations from developing fenugreek seed endosperms. Two enzymes interact: a GDP-mannose dependent (1-->4)-beta-D-mannan synthase and a UDP-galactose dependent (1-->6)-alpha-D-galactosyltransferase. The statistical distribution of galactosyl substituents along the mannan backbone, and the degree of galactose substitution of the primary product of galactomannan biosynthesis appear to be regulated by the specificity of the galactosyltransferase.

Fatty acid composition, eicosanoid production and permeability in skin tissues of rainbow trout (Oncorhynchus mykiss) fed a control or an essential fatty acid deficient diet.

Rainbow trout (Oncorhynchus mykiss) were fed either a control diet containing fish oil or an essential fatty acid (EFA) deficient diet containing only hydrogenated coconut oil and palmitic acid as lipid source (93.4% saturated fatty acids) for 14 weeks and the fatty acid compositions of individual phospholipid classes from skin and opercular membrane (OM) determined. The permeability of skin and OM to water and the production of eicosanoids in skin and gills challenged with the Ca2+ ionophore A23187 were also measured.

The effect of dietary lipid on polyunsaturated fatty acid metabolism in Atlantic salmon (Salmo salar) undergoing parr-smolt transformation.

The aim of this study was to measure the changes in lipid metabolism which occur during smoltification and seawater transfer in Atlantic salmon (Salmo salar). Duplicate groups of Atlantic salmon parr were fed diets containing either fish oil (FO) or a blend of linseed and rapeseed oils, vegetable oil (VO), from October (week 0) to seawater transfer in May (week 26). From May to August (weeks 26-43), all fish were fed a fish oil-containing diet.

Development of an in vitro model of essential fatty acid deficiency in fish cells.

Levels of eicosapentaenoic acid (EPA; 20:5, n-3) greatly exceed those of arachidonic acid (AA; 20:4, n-6) in the tissue phospholipids of most fish species. Despite this, it is 20:4, n-6-derived eicosanoids that are produced predominantly in fish cells. The development of an essential fatty acid (EFA)-deficient fish cell line would greatly assist the study of this selectivity and so several fish cell lines were cultured in EFA-deficient (EFAD) media.

Effects of dietary borage oil [enriched in γ-linolenic acid,18:3(n-6)] or marine fish oil [enriched in eicosapentaenoic acid,20:5(n-3)] on growth, mortalities, liver histopathology and lipid composition of juvenile turbot (Scophthalmus maximus).

A marine fish oil, Marinol K (MO) and borage oil (BO) were used to formulate diets relatively rich in eicosapentaenoic acid [EPA; 20:5(n-3)] and γ-linolenic acid [GLA; 18:3(n-6)], respectively. The diets were fed to duplicate groups of juvenile turbot (Scophthalmus maximus) of initial weight 1.4 g for a period of 12 weeks.

Diets rich in eicosapentaenoic acid and gamma-linolenic acid affect phospholipid fatty acid composition and production of prostaglandins E1, E2 and E3 in turbot (Scophthalmus maximus), a species deficient in delta 5 fatty acid desaturase.

Duplicate groups of juvenile turbot, (Scophthalmus maximus), were fed diets containing either Marinol K (MO), a marine fish oil rich in eicosapentaenoic acid (EPA; 20:5, n-3) or borage oil (BO), rich in gamma-linolenic acid (GLA; 18:3, n-6), for a period of 12 weeks. Individual phospholipid fatty acid compositions from hearts of fish fed BO had significantly more 18:2, n-6, GLA, 20:2, n-6, dihomo-gamma-linolenic acid (DHGLA; 20:3, n-6) and total n-6 polyunsaturated fatty acids (PUFA), but significantly less arachidonic acid (AA; 20:4, n-6), compared to fish fed MO. In both phosphatidylcholine (PC) and phosphatidylethanolamine (PE) from heart, the DHGLA was increased by over 50-fold in fish fed BO while AA was reduced by over two-thirds, compared to fish fed MO.

Effects of different dietary arachidonic acid : docosahexaenoic acid ratios on phospholipid fatty acid compositions and prostaglandin production in juvenile turbot (Scophthalmus maximus).

Five purified diets containing AA (20:4n-6) at 0.02-0.78% dry weight and DHA (22:6n-3) at 0.

Cortical layer-specific effects of the metabotropic glutamate receptor agonist 1S,3R-ACPD in rat primary somatosensory cortex in vivo.

The effects of iontophoretically applied (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD), a metabotropic glutamate receptor (mGluR) agonist, were studied on extracellularly recorded neurons throughout the depth of the primary somatosensory cortex in the anaesthetized adult rat. Distinct excitatory effects were found almost exclusively in neurons recorded in layer V. Postsynaptic depressant effects dominated neurons recorded in layers I-IV.

Effects of diets rich in linoleic (18:2n - 6) and α-linolenic (18:3n - 3) acids on the growth, lipid class and fatty acid compositions and eicosanoid production in juvenile turbot (Scophthalmus maximus L.).

Three practical-type diets utilizing fishmeal and casein as the protein sources and containing fish oil (FO), safflower oil (SO) or linseed oil (LO) were fed to duplicate groups of juvenile turbot (Scophthalmus maximus) of initial weight 1.2 g for a period of 12 weeks. No differences in final weight, mortality or development of pathological lesions were evident either between duplicate tanks or between dietary treatments over this period.

The effects of the metabotropic glutamate receptor agonist 1S,3R-ACPD on neurones in the rat primary somatosensory cortex in vivo.

The selective glutamate metabotropic receptor agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD) was applied iontophoretically to cells in the rat primary somatosensory cortex (SI) in vivo. In contrast to other in vivo studies, distinct excitatory and depressant effects were observed. The excitatory responses could not be blocked by ionotropic antagonists, as evidence that they were mediated by a metabotropic receptor.

Action of a pure xyloglucan endo-transglycosylase (formerly called xyloglucan-specific endo-(1-->4)-beta-D-glucanase) from the cotyledons of germinated nasturtium seeds.

The action on tamarind seed xyloglucan of the pure, xyloglucan-specific endo-(1-->4)-beta-D-glucanase from nasturtium (Tropaeolum majus L.) cotyledons has been compared with that of a pure endo-(1-->)-beta-D-glucanase ('cellulase') of fungal origin. The fungal enzyme hydrolysed the polysaccharide almost completely to a mixture of the four xyloglucan oligosaccharides: [formula: see text] Exhaustive digestion with the nasturtium enzyme gave the same four oligosaccharides plus large amounts of higher oligosaccharides and higher-polymeric material.

Elongation predominates over desaturation in the metabolism of 18:3n-3 and 20:5n-3 in turbot (Scophthalmus maximus) brain astroglial cells in primary culture.

The origin of docosahexaenoic acid (DHA, 22:6n-3) that accumulates in turbot brain during development was investigated by studying the incorporation and metabolism via the desaturase/elongase pathways of [1-14C]-labelled polyunsaturated fatty acids (PUFA) in primary cultures of brain astrocytic glial cells. There was little specificity evident in the total incorporation of PUFAs into the turbot astrocytes. However, specificity was apparent in the distribution of the various PUFAs among the individual lipid classes.