Search results for "ASTER"
showing 10 items of 2223 documents
Serotonin modulates a depression-like state in Drosophila responsive to lithium treatment
2016
Major depressive disorder (MDD) affects millions of patients; however, the pathophysiology is poorly understood. Rodent models have been developed using chronic mild stress or unavoidable punishment (learned helplessness) to induce features of depression, like general inactivity and anhedonia. Here we report a three-day vibration-stress protocol for Drosophila that reduces voluntary behavioural activity. As in many MDD patients, lithium-chloride treatment can suppress this depression-like state in flies. The behavioural changes correlate with reduced serotonin (5-HT) release at the mushroom body (MB) and can be relieved by feeding the antidepressant 5-hydroxy-L-tryptophan or sucrose, which …
Prevalence and determinants of post-traumatic stress disorder, anxiety and depression symptoms in street children survivors of the 2010 earthquake in…
2017
International audience; Working with street children and adolescents who lived through the 2010 earthquake in Port-au-Prince, this paper aims to assess the prevalence of symptoms of PTSD, anxiety and depression in relation to peritraumatic distress, and age, and to explore other risk factors and socio-demographic characteristics, four years after the events. Between March and June 2014, with a sample of 128 children and adolescents (120 boys and 8 girls) aged between 7 and 18, of an average age of 13.88 (SD = 2.15), all living on the streets of Port-au-Prince, we used the following scales: the Trauma Exposure (TE), the Life Events Subscale of the CAPS; the Peritraumatic Distress Inventory (…
Male relatedness and familiarity are required to modulate male-induced harm to females in
2017
Males compete over mating and fertilization, and often harm females in the process. Inclusive fitness theory predicts that increasing relatedness within groups of males may relax competition and discourage male harm of females as males gain indirect benefits. Recent studies in Drosophila melanogaster are consistent with these predictions, and have found that within-group male relatedness increases female fitness, though others have found no effects. Importantly, these studies did not fully disentangle male genetic relatedness from larval familiarity, so the extent to which modulation of harm to females is explained by male familiarity remains unclear. Here we performed a fully factorial des…
Inbreeding removes sex differences in lifespan in a population of Drosophila melanogaster
2016
Sex differences in ageing rates and lifespan are common in nature, and an enduring puzzle for evolutionary biology. One possibility is that sex-specific mortality rates may result from recessive deleterious alleles in ‘unguarded’ heterogametic X or Z sex chromosomes (the unguarded X hypothesis). Empirical evidence for this is, however, limited. Here, we test a fundamental prediction of the unguarded X hypothesis in Drosophila melanogaster, namely that inbreeding shortens lifespan more in females (the homogametic sex in Drosophila) than in males. To test for additional sex-specific social effects, we studied the lifespan of males and females kept in isolation, in related same-sex groups, and…
Participation and performance trends in 100-km ultra-marathons worldwide
2014
The aims of the present study were to (1) investigate the participation trends for the origin of athletes competing in 100-km ultra-marathons and (2) determine the nationalities of athletes achieving the fastest 100-km race times worldwide. Race times and nationality from 112,283 athletes (15,204 women and 97,079 men) from 102 countries who completed a 100-km ultra-marathon worldwide between 1998 and 2011 were investigated using single- and multi-level regression analyses. The number of finishers increased exponentially, both for women and men. Most of the finishers (73.5%) were from Europe, in particular, France (30.4%). The number of finishers from Japan, Germany, Italy, Poland and the Un…
''Limits in endurance performance of octogenarian athletes''
2013
TO THE EDITOR: A recent study of Trappe et al. (3) showed that the aerobic power of octogenarian lifelong endurance athletes was approximately double that of untrained octogenarians (38 vs. 21 ml·kg 1 ·min 1 ). These remarkable aerobic capacities are the highest ever recorded in this age group. However, the impact of the identified physiological capacities on actual endurance performances has not been addressed, as no running performance indicators of the octogenarian athletes were provided in this study. We hereby suggest that, although trained octogenarian athletes can achieve levels of aerobic fitness well above their untrained counterpart, as a group they actually have not yet reached t…
Trends in life satisfaction in European and North-American adolescents from 2002 to 2010 in over 30 countries
2015
Background: Life satisfaction (LS) is an indicator which is widely used for assessing the perception of a child's feeling about his life. Methods: LS is assessed in Health Behaviour in School-aged Children via the Cantril ladder with 10 steps indicating the worst and best possible life. This range of values (0-10) was dichotomized into 'low' (0-5) vs. 'high' (6-10). Countries, age groups and genders were compared based on the odds ratio (OR) of declaring a higher LS in 2010 with respect to 2002. Results: Analyzing the difference between 2002 and 2010, six countries from Western Europe show decreasing LS: Austria, Canada, Switzerland, Denmark, Finland and Greenland. In contrast, a group of E…
The Influence of the Hot Water Extract from Shiitake Medicinal Mushroom, Lentinus edodes (Higher Basidiomycetes) on the Food Intake, Life Span, and A…
2014
Shiitake medicinal mushroom, Lentinus edodes, is among the most widely cultivated edible mushrooms in the world and is a well-studied source of nutrients and biologically active compounds. We have studied the influence of the dietary supplement of the polysaccharides containing a hot water extract of the mushroom L. edodes on the fruit fly Drosophila melanogaster in terms of food intake, body weight, life span, and age-related locomotor activity. L. edodes extract, when added to the D. melanogaster feeding substrate at a 0.003-0.030% concentration (calculated for the dry weight of the polysaccharide fraction) did not influence food intake or body weight of the flies. It increased the life s…
Volatile Drosophila cuticular pheromones are affected by social but not sexual experience.
2012
International audience; Recognition of conspecifics and mates is based on a variety of sensory cues that are specific to the species, sex and social status of each individual. The courtship and mating activity of Drosophila melanogaster flies is thought to depend on the olfactory perception of a male-specific volatile pheromone, cis-vaccenyl acetate (cVA), and the gustatory perception of cuticular hydrocarbons (CHs), some of which are sexually dimorphic. Using two complementary sampling methods (headspace Solid Phase Micro-Extraction [SPME] and solvent extraction) coupled with GC-MS analysis, we measured the dispersion of pheromonal CHs in the air and on the substrate around the fly. We als…
Longitudinal assessment of health-span and pre-death morbidity in wild type
2018
The increase in human life expectancy is accompanied by age-related cognitive and motor disability, thus raising the demand for strategies toward healthy aging. This requires understanding the biology of normal aging and late-life functional phenotypes. Genetic model organisms, such as Drosophila melanogaster, can help identifying evolutionary conserved mechanisms underlying aging. Longitudinal assessment of motor performance of more than 1000 individual flies revealed age-related motor performance decline and specific late-life motor disabilities. This allows defining heath- and ill-span and scoring late-life quality of individual flies. As in mammals, including humans, onset, duration, se…