15 research outputs found
An Expressed Sequence Tag collection from the male antennae of the Noctuid moth Spodoptera littoralis: a resource for olfactory and pheromone detection research
<p>Abstract</p> <p>Background</p> <p>Nocturnal insects such as moths are ideal models to study the molecular bases of olfaction that they use, among examples, for the detection of mating partners and host plants. Knowing how an odour generates a neuronal signal in insect antennae is crucial for understanding the physiological bases of olfaction, and also could lead to the identification of original targets for the development of olfactory-based control strategies against herbivorous moth pests. Here, we describe an Expressed Sequence Tag (EST) project to characterize the antennal transcriptome of the noctuid pest model, <it>Spodoptera littoralis</it>, and to identify candidate genes involved in odour/pheromone detection.</p> <p>Results</p> <p>By targeting cDNAs from male antennae, we biased gene discovery towards genes potentially involved in male olfaction, including pheromone reception. A total of 20760 ESTs were obtained from a normalized library and were assembled in 9033 unigenes. 6530 were annotated based on BLAST analyses and gene prediction software identified 6738 ORFs. The unigenes were compared to the <it>Bombyx mori </it>proteome and to ESTs derived from Lepidoptera transcriptome projects. We identified a large number of candidate genes involved in odour and pheromone detection and turnover, including 31 candidate chemosensory receptor genes, but also genes potentially involved in olfactory modulation.</p> <p>Conclusions</p> <p>Our project has generated a large collection of antennal transcripts from a Lepidoptera. The normalization process, allowing enrichment in low abundant genes, proved to be particularly relevant to identify chemosensory receptors in a species for which no genomic data are available. Our results also suggest that olfactory modulation can take place at the level of the antennae itself. These EST resources will be invaluable for exploring the mechanisms of olfaction and pheromone detection in <it>S. littoralis</it>, and for ultimately identifying original targets to fight against moth herbivorous pests.</p
Les représentations de l'objet homéopathie chez les médecins. Une étude du projet Homeocss, projet d'étude sociétale sur la controverse autour de l'homéopathie
Dans le cadre du projet Homeocss, nous nous consacrons à l'étude de la controverse sociétale autour de l'homéopathie. Loin de l'idée de prendre position pour ou contre l'homéopathie, nous étudions les acteurs de cette controverse du point de vue sociologique et communicationnel. Dans l'étude présentée ici, nous avons interrogé des médecins, la plupart en exercice, acteurs majeurs de la controverse, au travers de questionnaires, dont nous analysons 244 réponses, complétés par une douzaine d'entretiens semi-directifs. Au sein de l'étude, nos résultats permettent d'identifier trois profils de médecins distincts : 1-des médecins défavorables à l'homéopathie, qui l'assimilent à un placebo pur et souvent à une escroquerie et qui prônent une médecine basée sur la science mais qui pratiquent parfois d'autres types de soins non conventionnels. Ces médecins sont relativement jeunes et utilisent fréquemment internet et les réseaux sociaux pour s'exprimer au sujet de l'homéopathie. 2-des médecins favorables à l'homéopathie, qui sont homéopathes ou qui prescrivent de l'homéopathie plus ou moins fréquemment, qui sont plus âgés et utilisent peu internet et les réseaux sociaux. Eux considèrent l'homéopathie comme une thérapeutique efficace, grâce à une action propre, ou plus rarement grâce à l'effet placebo, ou encore par un mécanisme qui reste à explorer. 3-des médecins « intermédiaires », qui généralement ne sont pas convaincus par une efficacité propre de l'homéopathie, mais qui pensent que son effet placebo est intéressant et constitue une alternative utile pour certains patients. En discussion, nous traiterons les questions de relations médecin-patient, de croyances et nous aborderons les stratégies de communication des médecins
Étude fonctionnelle et développementale des interactions entre le système visuel et l'horloge circadienne de Drosophila melanogaster
PARIS7-Bibliothèque centrale (751132105) / SudocSudocFranceF
A Role for Blind DN2 Clock Neurons in Temperature Entrainment of the Drosophila Larval Brain
Circadian clocks synchronize to the solar day by sensing the diurnal changes in light and temperature. In adult Drosophila, the brain clock that controls rest-activity rhythms relies on neurons showing Period oscillations. Nine of these neurons are present in each larval brain hemisphere. They can receive light inputs through Cryptochrome (CRY) and the visual system, but temperature input pathways are unknown. Here, we investigate how the larval clock network responds to light and temperature. We focused on the CRY-negative dorsal neurons (DN2s), in which light-dark (LD) cycles set molecular oscillations almost in antiphase to all other clock neurons. We first showed that the phasing of the DN2s in LD depends on the pigment-dispersing factor (PDF) neuropeptide in four lateral neurons (LNs), and on the PDF receptor in the DN2s. In the absence of PDF signaling, these cells appear blind, but still synchronize to temperature cycles. Period oscillations in the DN2s were stronger in thermocycles than in LD, but with a very similar phase. Conversely, the oscillations of LNs were weaker in thermocycles than in LD, and were phase-shifted in synchrony with the DN2s, whereas the phase of the three other clock neurons was advanced by a few hours. In the absence of any other functional clock neurons, the PDF-positive LNs were entrained by LD cycles but not by temperature cycles. Our results show that the larval clock neurons respond very differently to light and temperature, and strongly suggest that the CRY-negative DN2s play a prominent role in the temperature entrainment of the networ
Study on the cancer’s representations from primary school pupils and their filing systems
Proceedings of the 6th edition of the New Perspectives in Science Education Conference, Florence, March 16,-17, 2017International audienceRepresentation is an act of thought through which a subject relates to an object. There is no representation without an object. In order to comprehend the representation’s content, it is thus necessary to emphasize on the components from the representations which scientific information belongs to and that is of great interest for us on this study on cancer.This study aims to identify the cancer’s representations that 10 years old pupils possess (in Year 5). The variable taken into account in this study is the knowledge of cancer these young pupils have and its relative position compared with other illnesses. The sample is composed of 64 pupils from Year 5. The pieces of information were gathered from the filing systems intuitively established by the pupils (Intuitive classifying systems). A first questionnaire (pre-study) required listing the names of the illnesses that come straight to their minds. The second questionnaire suggested 4 features (contagious illness, fatal, curable with or without medicines) and asked to classify illnesses according to the latter.The results showed the strong importance of cancer in the pupils’ minds while they should feel less concerned about it, particularly because this subject is not seen at school at this age. Cancer is the most spontaneously quoted illness before influenza and HIV. It is perceived as non-contagious (For 92% of the pupils) but highly associated to death (89%) even though the chances of survival are higher than for the other illnesses evoked (HIV, influenza, Ebola) thanks to a treatment (30% of the answers). This relation to cancer seems to be correlated to the personal background of the pupils, who were touched by this illness in their close relations, as cancer is often presented as really serious without being explained with simple explanations. These results raised the importance of teaching and giving detailed information in the school or extracurricular environments to young people. It is hoped that such an education would demystify cancer