Molecular and physiological study of the artificial maturation process in European eel males: from brain to testis.

European eel males can be artificially matured (1.5IU hCG/g fish), but the regulatory mechanisms of their reproductive development are practically unknown. Spermatogenic stages (S1-S6), biometric characters [eye index (EI), gonadosomatic index (GSI), hepatosomatic index (HSI)] and sperm quality parameters (motility, viability and head spermatozoa morphometry) were analysed.

Beta1 integrins are required for the invasion of the caecum and proximal hindgut by enteric neural crest cells.

Integrins are the major adhesive receptors for extracellular matrix and have various roles in development. To determine their role in cell migration, the gene encoding the beta1 integrin subunit (Itgb1) was conditionally deleted in mouse neural crest cells just after their emigration from the neural tube. We previously identified a major defect in gut colonisation by conditional Itgb1-null enteric neural crest cells (ENCCs) resulting from their impaired migratory abilities and enhanced aggregation properties.

Regulation of net hepatic glycogenolysis and gluconeogenesis by epinephrine in humans.

The relative contributions of net hepatic glycogenolysis (NHG) and gluconeogenesis to rates of glucose production during a physiological increment in plasma epinephrine concentrations, independent of changes in plasma insulin concentrations, were determined in seven fasting, healthy young subjects. Plasma insulin concentrations were kept constant by infusing somatostatin (0.1 microg.

Control of puberty in farmed fish.

Puberty comprises the transition from an immature juvenile to a mature adult state of the reproductive system, i.e. the individual becomes capable of reproducing sexually for the first time, which implies functional competence of the brain-pituitary-gonad (BPG) axis.

Characterisation of Bombyx mori Odorant-binding proteins reveals that a general odorant-binding protein discriminates between sex pheromone components.

In many insect species, odorant-binding proteins (OBPs) are thought to be responsible for the transport of pheromones and other semiochemicals across the sensillum lymph to the olfactory receptors (ORs) within the antennal sensilla. In the silkworm Bombyx mori, the OBPs are subdivided into three main subfamilies; pheromone-binding proteins (PBPs), general odorant-binding proteins (GOBPs) and antennal-binding proteins (ABPs). We used the MotifSearch algorithm to search for genes encoding putative OBPs in B.

Behavioral and electrophysiological evidence for the impact of regional variation on phoneme perception.

This event-related potential (ERP) study examined the impact of phonological variation resulting from a vowel merger on phoneme perception. The perception of the /e/-/epsilon/ contrast which does not exist in Southern French-speaking regions, and which is in the process of merging in Northern French-speaking regions, was compared to the /ø/-/y/ contrast, which is stable in all French-speaking regions. French-speaking participants from Switzerland for whom the /e/-/epsilon/ contrast is preserved, but who are exposed to different regional variants, had to perform a same-different task.

Detection of the anti-androgenic effect of endocrine disrupting environmental contaminants using in vivo and in vitro assays in the three-spined stickleback.

We have previously developed a novel in vitro assay that utilises cultures of primed female stickleback kidney cells for the screening of potential androgenic and anti-androgenic environmental contaminants. Stickleback kidney cells are natural targets for steroid hormones and are able to produce a protein, spiggin, in response to androgenic stimulation. We undertook a combined in vivo/in vitro study where we used the magnitude of spiggin production as an endpoint to test the anti-androgenic properties of the pharmaceutical androgen antagonist flutamide and three environmental contaminants: the organophosphate insecticide fenitrothion, the urea-based herbicide linuron and the fungicide vinclozolin.

Orthographic influences in spoken word recognition: the consistency effect in semantic and gender categorization tasks.

According to current models, spoken word recognition is driven by the phonological properties of the speech signal. However, several studies have suggested that orthographic information also influences recognition in adult listeners. In particular, it has been repeatedly shown that, in the lexical decision task, words that include rimes with inconsistent spellings (e.

Competition effects in phonological priming: the role of mismatch position between primes and targets.

In three experiments, we examined lexical competition effects using the phonological priming paradigm in a shadowing task. Experiments 1A and 1B showed that an inhibitory priming effect occurred when the primes mismatched the targets on the last phoneme (/bagar/-/bagaj/). In contrast, a facilitatory priming effect was observed when the primes mismatched the targets on the medial phoneme (/viraj/-/vilaj/).

Role of E-cadherin in membrane-cortex interaction probed by nanotube extrusion.

This study aims to define the role of E-cadherin (Ecad) engagement in cell-cell contact during membrane-cortex interaction. As a tool, we used a hydrodynamic membrane tube extrusion technique to characterize the mechanical interaction between the plasma membrane and the underlying cortical cytoskeleton. Cells were anchored on 4.

Cortisol mobilizes mineral stores from vertebral skeleton in the European eel: an ancestral origin for glucocorticoid-induced osteoporosis?

Endogenous excess cortisol and glucocorticoid (GC) therapy are a major cause of secondary osteoporosis in humans. Intense bone resorption can also be observed in other vertebrates such as migratory teleost fish at the time of reproductive migration and during fasting when large amounts of calcium and phosphate are required. Using a primitive teleost, the European eel, as a model, we investigated whether cortisol could play an ancestral role in the induction of vertebral skeleton demineralization.

Vicia faba-Lygus rugulipennis interactions: induced plant volatiles and sex pheromone enhancement.

The profiles of volatile chemicals emitted by Vicia faba plants damaged by Lygus rugulipennis feeding, and by feeding plus oviposition, were shown to be quantitatively different from those released by undamaged plants. Samples of volatile chemicals collected from healthy plants, plants damaged by males as a consequence of feeding, plants damaged by females as a consequence of feeding and oviposition, plants damaged by feeding with mated males still present, and plants damaged by feeding and oviposition with gravid females still present, showed significant differences in the emission of hexyl acetate, (Z)-beta-ocimene, (E)-beta-ocimene, (E)-beta-caryophyllene, and methyl salicylate. In particular, treatments with mated females present on plants had a significant increase in emission levels of the above compounds, possibly due to eggs laid within plant tissues or active feeding, compared with undamaged plants and plants damaged by males feeding, with or without insects still present.

Surface properties of new virginiamycin M(1) derivatives.

Three kinds of derivatives of the M(1) factor of virginiamycin have been synthesised: esters with long chain fatty acids, oximes with modified polar amino acids and bis-derivatives with both the ester and oxime function. The study of the surface tension time dependence of M(1) and its derivatives has shown that it is necessary to enhance simultaneously the hydrophobicity and the hydrophilicity of M(1) to render M(1) surface-active. A structure/function relationship study of the surface-active bis-derivatives has shown that enhancing the hydrophobicity of the molecule led to slower adsorption kinetics, higher stability of the monolayers formed and a better capacity to penetrate a membrane model.

Two distinct dopamine D2 receptor genes in the European eel: molecular characterization, tissue-specific transcription, and regulation by sex steroids.

Two full-length cDNA encoding putative dopamine D2-like receptors were cloned from the brain of female European eel. The deduced protein sequences, termed D2A- and D2B-R, exhibit closer phylogenetic relationships to vertebrate D2 receptors compared with D3 and D4 or D1 receptors. The two protein sequences share 100% identity within the transmembrane domains containing the highly conserved amino acids involved in dopamine binding.

Visible minority, Aboriginal, and Caucasian children investigated by Canadian protective services.

The aim of this descriptive study was to compare the report profiles of Caucasian, Aboriginal, and other visible minority children whose cases were assessed by child protective services in Canada. The results show that children of Aboriginal ancestry and from visible minority groups are selected for investigation by child protective services 1.77 times more frequently than are children in the general population.

Increased substrate oxidation and mitochondrial uncoupling in skeletal muscle of endurance-trained individuals.

Endurance exercise training is accompanied by physiological changes that improve muscle function and performance. Several studies have demonstrated that markers of mitochondrial capacity are elevated, however, these studies tend to be performed ex vivo under conditions that yield maximal enzyme activities or in vivo but monitoring the response to exercise. Therefore, it is unclear whether basal mitochondrial metabolism is affected by exercise training.

Capns1, a new binding partner of RasGAP-SH3 domain in K-Ras(V12) oncogenic cells: modulation of cell survival and migration.

Ras GTPase-activating protein (RasGAP) is hypothesized to be an effector of oncogenic Ras stimulating numerous downstream cellular signaling cascades involved in survival, proliferation and motility. In this study, we identified calpain small subunit-1 (Capns1) as a new RasGAP-SH3 domain binding partner, using yeast two-hybrid screening. The interaction was confirmed by co-immunoprecipitation assay and was found specific to cells expressing oncogenic K-Ras.

A RasGAP SH3 peptide aptamer inhibits RasGAP-Aurora interaction and induces caspase-independent tumor cell death.

The Ras GTPase-activating protein RasGAP catalyzes the conversion of active GTP-bound Ras into inactive GDP-bound Ras. However, RasGAP also acts as a positive effector of Ras and exerts an anti-apoptotic activity that is independent of its GAP function and that involves its SH3 (Src homology) domain. We used a combinatorial peptide aptamer approach to select a collection of RasGAP SH3 specific ligands.

How cadmium could compromise the completion of the European eel's reproductive migration.

The European eel (Anguilla anguilla L.) is severely threatened with extinction. Surprisingly, even though their unusual life cycle makes them particularly vulnerable to pollution, the possible contribution of contamination remains especially poorly known.

Identification of volatile compounds used in host location by the black bean aphid, Aphis fabae.

Behavioral and electrophysiological responses of winged Aphis fabae to volatiles of faba bean, Vicia faba (var. Sutton dwarf), plants were studied and semiochemicals used in host location were identified. In olfactometer bioassays, aphids spent significantly more time in the region of the olfactometer where V.

Phonological priming in auditory word recognition: when both controlled and automatic processes are responsible for the effects.

The phonological priming paradigm provides an interesting methodological tool for studying various components of the speech recognition process. However, concerns about response biases distorting the effects have been repeatedly voiced. This article reviews the main studies on priming and aims to distinguish effects under automatic processes from those under some level of strategic control.

Nanoscale membrane activity of surfactins: influence of geometry, charge and hydrophobicity.

We used real-time atomic force microscopy (AFM) to visualize the interactions between supported lipid membranes and well-defined surfactin analogs, with the aim to understand the influence of geometry, charge and hydrophobicity. AFM images of mixed dioleoylphosphatidylcholine/dipalmitoylphosphatidylcholine (DOPC/DPPC) bilayers recorded after injection of cyclic surfactin at 1 mM, i.e.