Search results for "longevity."
showing 10 items of 373 documents
MEDITERRANEAN DIET AND LIFESTYLE: A PROVED APPROACH TO HEALTHY LONGEVITY
2017
Aging is a multifactorial and progressive process, universal and irreversible, that takes place at different levels, affecting practically all-living organisms. Human life expectancy increased extraordinarily during the last century worldwide. Currently, there is growing evidence that there are modifiable factors that contribute to ageing per se, and particularly to longevity (i.e. diet, physical and mental activity). These factors may interact with the ageing process and may alter the susceptibility of an individual to develop age-associated diseases. There is currently much promise in research that provides information about the underlying biology of ageing and longevity, which has unveil…
LONGEVITY AND THE SECRETS OF CENTENARIANS
2017
Aging of the world populations represents one of the most remarkable success stories of medicine and of humankind. Hence, the search for ways to prolong health expectancy is a primary goal in medicine. Human life expectancy increased extraordinarily during the last century worldwide. Life expectancy at birth has almost doubled in most developed countries over the last century, with the oldest group being the most rapidly growing segment of the population. The number of centenarians in Italy is over 16.000 and the number is over tripled in few years (they were 5.000 in 2001). Among older population, centenarians may be considered the best example of successful aging. The capacity to avoid, d…
MANAGING LEVERS OF ORGANIZATION DESIGN TO ENHANCE SMES’ LONGEVITY: An Agenda for Further Research
2012
SME success is often primarily linked to the personal traits of entrepreneurs and vice versa. In terms of SME failure, most of the literature, research and popular press, seems focused on individual factors, such as those related to the owner/entrepreneur’s profile and behavior, or contextual factors like those associated with relationships between the firm and its own stakeholders, especially on the competitive and financial systems arenas. That said, some scholars have emphasized the relevance of organizational design for SME longevity, though there seems to be little inter-relating of the two sides. This paper examines the relationships between owner/entrepreneur attributes and organizat…
Senescence and longevity : from physiological mechanisms to evolutionary processes : studies in birds and mammals
2012
There is an incredible diversity of lifespan in the animal kingdom ranging from a few days for small gastrotrichs worms to several hundred of years for some bivalves or tortoises. This amazing diversity has long questioned biology researchers. The growing interest in the phenomenon of aging, mainly due to the increase in life expectancy in humans, has questioned researchers on processes that determine patterns of longevity and ageing. On the one hand, biomedical and biogerontological studies helped describe numerous cellular and physiological mechanisms related to aging. Among these mechanisms, oxidative stress has been identified as playing a major role, through life-time accumulation of d…
Effects of temperature and desiccation on ex situ conservation of nongreen fern spores
2012
Premise of the study Fern spores are unicellular and haploid, making them a potential model system to study factors that regulate lifespan and mechanisms of aging. Aging rates of nongreen spores were measured to compare longevity characteristics among diverse fern species and test for orthodox response to storage temperature and moisture. Methods Aging of spores from 10 fern species was quantified by changes in germination and growth parameters. Storage temperature ranged from ambient room to -196°C (liquid nitrogen); spores were dried to ambient relative humidity (RH) or using silica gel. Key results Survival of spores varied under ambient storage conditions, with one species dying within …
Starvation endurance in the antTemnothorax nylanderidepends on group size, body size and access to larvae
2013
Social interactions in animal groups can buffer environmental stress and may enhance survival under unfavourable conditions. In the present study, the impact on starvation endurance of social group, access to larvae and cold shock is studied in the ant Temnothorax nylanderi Forster. Resource sharing is expected to lead to grouped workers surviving longer than isolated ones. Access to larvae may increase longevity if larvae serve as food, or may interfere with survival if they induce caring behaviour in workers. Cold shock serves as a stress factor and a negative influence on survival is expected. The results show that isolated workers have a shorter lifespan than grouped workers, which in t…
Queen loss increases worker survival in leaf-cutting ants under paraquat-induced oxidative stress
2021
Longevity is traded off with fecundity in most solitary species, but the two traits are positively linked in social insects. In ants, the most fecund individuals (queens and kings) live longer than the non-reproductive individuals, the workers. In many species, workers may become fertile following queen loss, and recent evidence suggests that worker fecundity extends worker lifespan. We postulated that this effect is in part owing to improved resilience to oxidative stress, and tested this hypothesis in three Myrmicine ants: Temnothorax rugatulus, and the leaf-cutting ants Atta colombica and Acromyrmex echinatior . We removed the queen from colonies to induce worker reproduction and subjec…
Toxicological assessment of mesoporous silica particles in the nematode Caenorhabditis elegans
2018
[EN] Here we report the toxicological evaluation of mesoporous silica particles (MSPs) in the nematode C. elegans. Specifically, we have investigated the effect of bare micro- (M0) and nano-sized (N0) MSPs, and their corresponding functionalized particles with a starch derivative (Glu-N) (M1 and N1, respectively) on C. elegans ageing parameters. The toxicity of MSPs, their impact on C. elegans lifespan, movement capacity, progeny and ability to survive upon exposure to acute oxidative stress were assessed. This study demonstrated that both size particles assayed (M0 and N0), labeled with rhodamine and monitored through fluorescence microscopy, are ingested by the nematode. Moreover, toxicit…
Serine- and Threonine/Valine-Dependent Activation of PDK and Tor Orthologs Converge on Sch9 to Promote Aging
2014
Dietary restriction extends longevity in organisms ranging from bacteria to mice and protects primates from a variety of diseases, but the contribution of each dietary component to aging is poorly understood. Here we demonstrate that glucose and specific amino acids promote stress sensitization and aging through the differential activation of the Ras/cAMP/PKA, PKH1/2 and Tor/S6K pathways. Whereas glucose sensitized cells through a Ras-dependent mechanism, threonine and valine promoted cellular sensitization and aging primarily by activating the Tor/S6K pathway and serine promoted sensitization via PDK1 orthologs Pkh1/2. Serine, threonine and valine activated a signaling network in which Sch…
Effect of water content and temperature on seed longevity of seven Brassicaceae species after 5 years of storage.
2014
Maximising seed longevity is crucial for genetic resource preservation and longevity of orthodox seeds is determined by environmental conditions (water content and temperature). The effect of water content (down to 0.01 g·H₂O·g(-1) ) on seed viability was studied at different temperatures for a 5-year storage period in taxonomically related species. Seeds of seven Brassicaceae species (Brassica repanda, Eruca vesicaria, Malcolmia littorea, Moricandia arvensis, Rorippa nasturtium-aquaticum, Sinapis alba, Sisymbrium runcinatum) were stored at 48 environments comprising a combination of eight water contents, from 0.21 to 0.01 g·H₂O·g(-1) DW and six temperatures (45, 35, 20, 5, -25, -170 °C). S…