Search results for "larvae"
showing 6 items of 66 documents
Visual Contrast Modulates Operant Learning Responses in Larval Zebrafish.
2018
The larval zebrafish is a promising vertebrate model organism to study neural mechanisms underlying learning and memory due to its small brain and rich behavioral repertoire. Here, we report on a high-throughput operant conditioning system for zebrafish larvae, which can simultaneously train 12 fish to associate a visual conditioned pattern with electroshocks. We find that the learning responses can be enhanced by the visual contrast, not the spatial features of the conditioned patterns, highlighted by several behavioral metrics. By further characterizing the learning curves as well as memory extinction, we demonstrate that the percentage of learners and the memory length increase as the co…
Fire benefits flower beetles in a Mediterranean ecosystem
2018
Despite the abundance of plants that benefit from fire in Mediterranean ecosystems, little is known about the possible presence of fire-favoured insects (other than bark beetles). For two years we sampled invertebrates after two large wildfires in eastern Spain and demonstrate that two flower beetle species, Protaetia morio and P. oblonga (Cetoniidae), show a pyrophilous behaviour. These beetles were much more numerous after the fires than in unburnt plots around the fire perimeter; in addition, these species tended to increase in number with the distance from the fire perimeter and with fire recurrence, especially P. morio. These results were maintained for the two postfire years sampled. …
Elie Metchnikoff and the multidisciplinary link novelty among Zoology, Embryology and Innate Immunity
2018
Elie Metchnikoff was a Russian scientist known as the pioneer of innate immunity. In particular, he was awarded the Nobel Prize for discovering the process of phagocytosis and its significance in the development and disease. Here, we endeavor to demonstrate the enduring fascination of his scientific research, in particular the experiment involving the first observation of a macrophage reaction in the sea star. This applies to both adult and larvae immunity studies. Recent work on sea star larval cellular immunity and adult immune systems using modern expansions of molecular and cellular techniques shows that it is a continually exciting research field that cannot just be consigned to histor…
Host-range expansion of Spodoptera exigua multiple nucleopolyhedrovirus to Agrotis segetum larvae when the midgut is bypassed.
2010
Given the high similarity in genome content and organization between Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) and Agrotis segetum nucleopolyhedrovirus (AgseNPV), as well as the high percentages of similarity found between their 30 core genes, the specificity of these NPVs was analysed for the respective insect hosts, S. exigua and A. segetum. The LD(50) for AgseNPV in second-instar A. segetum larvae was 83 occlusion bodies per larva and the LT(50) was 8.1 days. AgseNPV was orally infectious for S. exigua, but the LD(50) was 10 000-fold higher than for SeMNPV. SeMNPV was not infectious for A. segetum larvae when administered orally, but an infection was established by injecti…
Anticancer Agents: Does a Phosphonium Behave Like a Gold(I) Phosphine Complex? Let a “Smart” Probe Answer!
2015
Gold phosphine complexes, such as auranofin, have been recognized for decades as antirheumatic agents. Clinical trials are now underway to validate their use in anticancer or anti-HIV treatments. However, their mechanisms of action remain unclear. A challenging question is whether the gold phosphine complex is a prodrug that is administered in an inactive precursor form or rather that the gold atom remains attached to the phosphine ligand during treatment. In this study, we present two novel gold complexes, which we compared to auranofin and to their phosphonium analogue. The chosen ligand is a phosphine-based smart probe, whose strong fluorescence depends on the presence of the gold atom. …
Phylogenetic analysis of cryptic speciation in the polychaete Pygospio elegans
2012
Development in marine invertebrate species can take place through a variety of modes and larval forms, but within a species, developmental mode is typically uniform. Poecilogony refers to the presence of more than one mode of development within a single species. True poecilogony is rare, however, and in some cases, apparent poecilogony is actually the result of variation in development mode among recently diverged cryptic species. We used a phylogenetic approach to examine whether poecilogony in the marine polychaete worm, Pygospio elegans, is the result of cryptic speciation. Populations of worms identified as P. elegans express a variety of developmental modes including planktonic, broode…