Search results for "Feeding"
showing 10 items of 861 documents
Neoclerodanes from Teucrium orientale
2004
Abstract Two new neoclerodane diterpenoids, 6-deacetyl-teucrolivin A (5) and 8beta-hydroxy-teucrolivin B (6), were isolated from the aerial parts of Teucrium orientale, along with four already known neoclerodane diterpenoids, teucrolivin A (1), teucrolivin B (2), teucrolivin C (3) and teucrolivin H (4), previously isolated from Teucrium oliverianum. Their structures were elucidated on the basis of spectroscopic evidence and chemical transformations. Compounds 1-3 were assayed for antifeedant activity against Spodoptera littoralis, S. frugiperda and Heliocoverpa armigera. Teucrolivin A was the most potent of the three compounds tested.
Factors affecting abundance of Triaenophorus infection in Cyclops strenuus, and parasite-induced changes in host fitness.
2000
Factors affecting the abundance of Triaenophorus crassus and Triaenophorus nodulosus procercoids in their copepod first intermediate host, Cyclops strenuus, and effects of infection on feeding behaviour, reproduction and survival of the host were studied experimentally. When exposed to the same number of coracidia, copepods harboured considerably less procercoids in the trials where ciliates or Artemia salina nauplii were given as alternative food items. The prevalence of infection was higher in adult copepods as compared with copepodite stage IV and stage V, and higher in stage V than in stage IV. The prevalences in adult females and males did not differ significantly from each other. The …
Volatiles in pantellerite magmas: A case study of the Green Tuff Plinian eruption (Island of Pantelleria, Italy)
2013
Abstract The Green Tuff (GT) Plinian eruption, the largest in magnitude at Pantelleria, erupted 3 to 7 km3 DRE of pantellerite magma and a small volume of trachyte. Fifty-nine anorthoclase-hosted melt inclusions from the two basal pumice members were analyzed by FT-IR spectroscopy in order to assess the pre-eruptive H2O content in the pantellerite melt. Microanalytical methods were used to determine major element, Cl, F and S contents. Melt inclusions and glassy groundmasses have a nearly homogeneous pantelleritic composition (peralkaline index = 1.9-2.2) and variable water contents ranging from 1.4 to as high as 4.2 wt %, i.e. much higher than the 1.4 wt % of earlier published studies. The…
Leptin and the central control of feeding behavior.
2012
International audience; The discovery of leptin by Friedman and coll. in 1995 was a major step forward in our comprehensive view of energy homeostasis. Since the original paper, a tremendous amount of work has been performed in laboratories all over the world. Many recent reviews have described this work in details. In the present review, we focus on the role of leptin on food intake. It is accepted by most authors working in this field that the control of food intake can be divided in two closely-related system: the homeostatic system and the hedonic system. Leptin has been shown to act on both systems.
Clusterin and LRP2 are critical components of the hypothalamic feeding regulatory pathway.
2012
Hypothalamic feeding circuits are essential for the maintenance of energy balance. There have been intensive efforts to discover new biological molecules involved in these pathways. Here we report that central administration of clusterin, also called apolipoprotein J, causes anorexia, weight loss and activation of hypothalamic signal transduction-activated transcript-3 in mice. In contrast, inhibition of hypothalamic clusterin action results in increased food intake and body weight, leading to adiposity. These effects are likely mediated through the mutual actions of the low-density lipoprotein receptor-related protein-2, a potential receptor for clusterin, and the long-form leptin receptor…
Behavioral profile of intermittent vs continuous access to a high fat diet during adolescence
2018
Abstract Over the past few years, the effects of a high-fat diet (HFD) on cognitive functions have been broadly studied as a model of obesity, although no studies have evaluated whether these effects are maintained after the cessation of this diet. In addition, the behavioral effects of having a limited access to an HFD (binge-eating pattern) are mostly unknown, although they dramatically increase the vulnerability to drug use in contrast to having continuous access. Thus, the aim of the present study was to compare the effects of an intermittent versus a continuous exposure to an HFD during adolescence on cognition and anxiety-like behaviors, as well as to study the changes observed after …
New Insights into the Functional Morphology of the Lever Mechanism of Salvia pratensis (Lamiaceae)
2007
† Background and Aims The functional morphology of Salvia pratensis flowers was re-investigated, after new insights revealed that pollen dispensing is one of the main functions of the staminal lever. In particular, no detailed information was available regarding the process of pollen transfer and the forces arising between the pollen-bearing thecae and the pollinating bee’s body. The assumption was made that these forces play a significant role in pollen dispensing. † Methods The functional morphology of S. pratensis flowers and the interaction between flowers and bees (Apis mellifera) were studied by reconstructing stress and strains by using qualitative and semi-quantitative theoretical a…
Assessing the Cost of Mounting an Immune Response
2003
International audience; The evolution of parasite resistance has often been assumed to be governed by antagonistic selection pressures. Defense against pathogens, by mounting an immune response, confers evident benefits but may also incur costs, so that the optimal level of defense is expected to depend on the balance between benefits and costs. Although the benefits of immune surveillance are well known, estimates of costs are still equivocal. Here we studied the behavioral and physiological modifications associated with exposure to a onreplicating antigen (lipopolysaccharide [LPS] of Escherichia coli) in a passerine species, the house sparrow (Passer domesticus).We further investigated wh…