Search results for "Attractant"
showing 10 items of 56 documents
Genetic feminization of pheromones and its behavioral consequences in Drosophila males
1997
0036-8075 (Print) Journal Article Research Support, Non-U.S. Gov't; Pheromones are intraspecific chemical signals important for mate attraction and discrimination. In the fruit fly Drosophila melanogaster, hydrocarbons on the cuticular surface of the animal are sexually dimorphic in both their occurrence and their effects: Female-specific molecules stimulate male sexual excitation, whereas the predominant male-specific molecule tends to inhibit male excitation. Complete feminization of the pheromone mixture produced by males was induced by targeted expression of the transformer gene in adult oenocytes (subcuticular abdominal cells) or by ubiquitous expression during early imaginal life. The…
Intraspecific Communication Through Chemical Signals in Female Mice: Reinforcing Properties of Involatile Male Sexual Pheromones
2006
In rodents, social and reproductive behaviors critically depend on chemical signals, including sexual pheromones that have been suggested (but not demonstrated) to be rewarding. In this work, we analyze this issue by studying the chemoinvestigatory behavior of adult female mice (without experience with male-derived chemicals) toward 1) the synthetic odorant citralva, 2) bedding soiled by different conspecifics (females, males, and castrated males), and 3) volatiles derived from bedding soiled by males and castrated males (confronted in 2-choice tests). We also study whether these chemical signals are able to induce conditioned place preference, a reliable test for rewarding properties of st…
Genetic feminization of brain structures and changed sexual orientation in male Drosophila
1995
0036-8075 (Print) Journal Article Research Support, Non-U.S. Gov't; The neural basis of sexual orientation in Drosophila was studied by the production of males with regionally feminized brains. Such flies express the female form of the sex determination gene transformer in a limited number of neurons under the control of GAL4 enhancer trap inserts. This method facilitated the creation of lines with a stable pattern of feminization. In tests of sexual preferences, flies that were feminized in a portion of the antennal lobes or in a subset of the corpora pedunculata (mushroom bodies) courted both males and females. These two brain structures, both of which are involved in olfactory processing…
Prostacyclin inhibits adhesion of polymorphonuclear leukocytes to human vascular endothelial cells due to adhesion molecule independent regulatory me…
2002
Prostacyclin is an important endothelial mediator involved in the interaction of neutrophils (PMN) with the vessel wall. Many studies have shown the beneficial effects of prostacyclin in ischemia and reperfusion. However, no previous study has investigated the direct effects of the prostacyclin analogs iloprost (ILO) and alprostadil (PGE(1)) on the endothelial part of the adhesion process. Human umbilical vein endothelial cells (HUVECs) were grown to confluence, stimulated with 300 U/ml TNF-alpha and treated with increasing concentrations of ILO and PGE(1). The cells were washed to remove TNF and the inhibitors and adhesion of fluorescence-green labeled PMN was determined microscopically. I…
Genetic study of the production of sexually dimorphic cuticular hydrocarbons in relation with the sex-determination gene transformer in Drosophila me…
2002
In Drosophila melanogaster, the main cuticular hydrocarbons (HCs) are some of the pheromones involved in mate discrimination. These are sexually dimorphic in both their occurrence and their effects. The production of predominant HCs has been measured in male and female progeny of 220 PGal4 lines mated with the feminising UAS-transformer transgenic strain. In 45 lines, XY flies were substantially or totally feminised for their HCs. Surprisingly, XX flies of 14 strains were partially masculinised. Several of the PGal4 enhancer-trap variants screened here seem to interact with sex determination mechanisms involved in the control of sexually dimorphic characters. We also found a good relationsh…
Effectiveness of mass trapping by bottle traps baited with salt sardines to control Bactrocera oleae (Gmelin)
2007
Various substances are known as attractants of tephritid flies; the putrescine and other compounds coming from animal decay have been positively tested for attraction of Bactrocera cucurbitae (Coquillett) and other tephritids. In Sicilian coastal areas, usually heavily infested by Bactrocera oleae (Gmelin), few organic farmers producing high quality olive oil apply mass trapping by using bottle traps baited with salt sardines. The aim of this paper is to test the effectiveness of this kind of mass trapping to control the olive fruit fly. In 2005 and 2006 mass trapping was tested in an organic olive grove (Cerasuola cultivar) located in Trapani. In 2005 two plots were delineated: 189 untreat…
Sexual pheromones and the evolution of the reward system of the brain: the chemosensory function of the amygdala.
2008
The amygdala of all tetrapod vertebrates receives direct projections from the main and accessory olfactory bulbs, and the strong similarities in the organization of these projections suggest that they have undergone a very conservative evolution. However, current ideas about the function of the amygdala do not pay sufficient attention to its chemosensory role, but only view it as the core of the emotional brain. In this study, we propose that both roles of the amygdala are intimately linked since the amygdala is actually involved in mediating emotional responses to chemical signals. The amygdala is the only structure in the brain receiving pheromonal information directly from the accessory …
Sex-pairing pheromones and reproductive isolation in three sympatric Cornitermes species (Isoptera, Termitidae, Syntermitinae)
2011
International audience; The species-specificity of pairing has been studied in three sympatric Neotropical termites: Cornitermes bequaerti, Cornitermes cumulans and Cornitermes silvestrii (Termitidae, Syntermitinae). Bioassays showed that sex attraction was highly species-specific between C. bequaerti and C cumulans but not between C. cumulans and C. silvestrii. The sex-pairing pheromone of the three species is secreted by the tergal glands of female alates. It consists of a common compound (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol. In C. bequaerti, this polyunsaturated alcohol is the only compound of the sex-pairing pheromone, whereas it is associated with the oxygenated sesquiterpene (E)-nerolid…
Study of mechanisms of action of an immunotherapy by triacyl lipid A in humans
2013
Immunotherapy acting at the primary tumor site and preventing the development of metastases is one of the strategies for treatment of patients with cancer. To improve the efficiency of the latter, it is necessary to understand how it induces tumor cell death. In the laboratory, it was observed the cure of PROb tumors in rats BDIX by the triacyl lipid A. It has been shown that this effect involved the immune system involving interactions with TLRs present in many tumor cells and innate immunity cells such as neutrophils.In this work, we investigated the possible involvement of neutrophils in the antitumor activity of triacyl lipid A in humans.In a Phase 1 study in patients with refractory so…
Simultaneous influence on male courtship of stimulatory and inhibitory pheromones produced by live sex-mosaic Drosophila melanogaster
1996
0962-8452 (Print) Journal Article Research Support, Non-U.S. Gov't; Stable strains of Drosophila melanogaster flies producing mosaic sex-pheromones were created by manipulating the sex-determination gene transformer in different cellular patterns. Chromosomally male flies produced molecules that were partly or totally feminized, depending upon the strain. The influence on male courtship behaviour of live flies producing different mixtures of male and female pheromones was measured. The intensity of the male response was mainly a function of the stimulatory effect of 7, 11 nonacosadiene and 7, 11 heptacosadiene, two female pheromones, combined with the inhibiting effect of 7-tricosene, the m…