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Extreme longevity

Alice Séguret, Abel Bernadou, Robert J Paxton
In eusocial insects, reversal of the fecundity/longevity trade-off and extreme differences in life histories between castes of the same species garner scientific and public interest. Facultative social species at the threshold of sociality, in which individuals are socially plastic, provide an excellent opportunity to understand the causes and mechanisms underlying this reversal in life history trade-off associated with eusociality. We briefly present the ultimate factors favoring sociality and the association between fecundity and longevity in facultative eusocial insects, including kin selection and disposable soma, as well as proximate mechanisms observed in such species, such as differences in hormone titers and functions...
August 2016: Current Opinion in Insect Science
Jane de Verges, Volker Nehring
Social insects have received attention for their extreme lifespan variation and reversal of the fecundity/longevity trade-off. However, proximate causes of senescence in general are disputed, and social insects often fail to meet the predictions of prevailing models. We present evidence for and against the long-held free radical theory of aging in social insects, and consider the application of the competing hyperfunction theory. Current results present problems for both theories, and a more complex picture of the biological processes involved emerges...
August 2016: Current Opinion in Insect Science
Jürgen Heinze
Perennial social insects are famous for the extraordinary longevity of their queens. While the lifespan of termite kings matches those of queens, males of social Hymenoptera are usually considered to die after one or a few copulations. While this is true in species with highly synchronized nuptial flights, in others males mate over much longer periods. Male longevity is not correlated with the life span of queens but appears to be adapted to mating opportunities. This is demonstrated by the extreme life span of Cardiocondyla ant males, which monopolize mating with virgin queens over many months...
August 2016: Current Opinion in Insect Science
R S Waples
Theory and empirical estimates agree that the ratio of effective size (Ne ) to census size (N) falls roughly in the range 0·1-0·5 for most populations. In a number of marine species, however, genetic estimates of contemporary Ne /N are as much as 5-6 orders of magnitude lower. Although some mechanisms that could produce such tiny Ne /N ratios have been proposed, the subject remains controversial. This issue is important to resolve: if Ne /N can be 10(-3) or smaller, marine fish populations that are quite large could be at genetic risk...
October 7, 2016: Journal of Fish Biology
M L van Pelt, V Ducrocq, G de Jong, M P L Calus, R F Veerkamp
Genetic correlations and heritabilities for survival were investigated over a period of 25 yr to evaluate if survival in first lactation has become a different trait and if this is affected by adjusting for production level. Survival after first calving until 12 mo after calving (surv_12mo) and survival of first lactation (surv_1st_lac) were analyzed in Dutch black-and-white cows. The data set contained 1,108,745 animals for surv_12mo and 1,062,276 animals for surv_1st_lac, with first calving between 1989 and 2013...
September 28, 2016: Journal of Dairy Science
Elizabeth E Devore, Stephanie L Harrison, Katie L Stone, Kathleen F Holton, Elizabeth Barrett-Connor, Sonia Ancoli-Israel, Kristine Yaffe, Kristine Ensrud, Peggy M Cawthon, Susan Redline, Eric Orwoll, Eva S Schernhammer
BACKGROUND: Circadian disruptions can contribute to accelerated aging, and the circadian system regulates cognitive and physical functions; therefore, circadian markers (eg, melatonin) may be associated with key aspects of healthy aging and longevity. OBJECTIVE: To evaluate urinary melatonin levels in relation to cognitive function, physical function, and mortality among 2,821 older men in the Osteoporotic Fractures in Men Study DESIGN: Cohort study. MEASUREMENTS: In 2003-2005, participants provided first-morning spot urine samples, which were assayed for 6-sulfatoxymelatonin (the primary melatonin metabolite in urine); cognitive and physical function assessments were completed twice, at baseline and an average of 6...
July 2016: Sleep Medicine
Haichen Yin, Qihao Shi, Muhammad Shakeel, Jing Kuang, Jianhong Li
Melanization reflects not only body color variation but also environmental plasticity. It is a strategy that helps insects adapt to environmental change. Different color morphs may have distinct life history traits, e.g., development time, growth rate, and body weight. The green slender planthopper Saccharosydne procerus (Matsumura) is the main pest of water bamboo (Zizania latifolia). This insect has two color morphs. The present study explored the influence of photoperiod and its interaction with temperature in nymph stage on adult melanism...
2016: Frontiers in Physiology
M Vasudevan, C D Johnston, T P Bastow, G Lekmine, J L Rayner, I M Nambi, G Suresh Kumar, R Ravi Krishna, G B Davis
The extent of dissolution of petroleum hydrocarbon fuels into groundwater depends greatly on fuel composition. Petroleum fuels can consist of thousands of compounds creating different interactions within the non-aqueous phase liquid (NAPL), thereby affecting the relative dissolution of the components and hence a groundwater plume's composition over long periods. Laboratory experiments were conducted to study the variability in the effective solubilities and activity coefficients for common constituents of gasoline fuels (benzene, toluene, p-xylene and 1,2,4-trimethylbenzene) (BTX) in matrices with an extreme range of molar volumes and chemical affinities...
September 20, 2016: Journal of Contaminant Hydrology
Marco T Tejeda, José Arredondo, Pablo Liedo, Diana Pérez-Staples, Patricia Ramos-Morales, Francisco Díaz-Fleischer
Species that exhibit broad ranges of distribution may successfully navigate environmental changes by modifying some of their life-history traits. Environmental humidity imposes a critical stress that organisms may overcome by increasing their resistance to desiccation. We used experimental evolution to investigate adaptation to desiccation in the tephritid Anastrepha ludens, a species with high fecundity, late maturation, and long lifespan. We measured morphological, physiological, developmental as well as demographic changes involved in the adaptation to desiccation...
September 18, 2016: Evolution; International Journal of Organic Evolution
Anna Picca, Vito Pesce, Giuseppe Sirago, Flavio Fracasso, Christiaan Leeuwenburgh, Angela Maria Serena Lezza
Extremely interesting for aging research are those individuals able to reach older ages still with functions similar to those of younger counterparts. We examined liver samples from ad libitum-fed old (28-month-old, AL-28) and ad libitum-fed very old (32-month-old, AL-32) rats for a number of markers, relevant for mitochondrial functionality and mitochondrial DNA (mtDNA) content. As for the mtDNA content and the protein amounts of the citrate synthase and the antioxidant peroxiredoxin III there were no significant changes in the AL-32 animals...
September 13, 2016: Experimental Gerontology
Marcello Pinti, Victor Appay, Judith Campisi, Daniela Frasca, Tamas Fülöp, Delphine Sauce, Anis Larbi, Birgit Weinberger, Andrea Cossarizza
Major advances in preventing, delaying, or curing individual pathologies are responsible for an increasingly long life span in the developed parts of our planet, and indeed reaching eight to nine decades of life is nowadays extremely frequent. However, medical and sanitary advances have not prevented or delayed the underlying cause of the disparate pathologies occurring in the elderly: aging itself. The identification of the basis of the aging processes that drives the multiple pathologies and loss of function typical of older individuals is a major challenge in current aging research...
October 2016: European Journal of Immunology
Masaki Takao, Nobuyoshi Hirose, Yasumichi Arai, Ban Mihara, Masaru Mimura
Supercentenarians (aged 110 years old or more) are extremely rare in the world population (the number of living supercentenarians is estimated as 47 in the world), and details about their neuropathological information are limited. Based on previous studies, centenarians (aged 100-109 years old) exhibit several types of neuropathological changes, such as Alzheimer's disease and Lewy body disease pathology, primary age-related tauopathy, TDP-43 pathology, and hippocampal sclerosis. In the present study, we provide results from neuropathological analyses of four supercentenarian autopsy cases using conventional and immunohistochemical analysis for neurodegenerative disorders...
2016: Acta Neuropathologica Communications
K Kawazu, W Sugeno, A Mochizuki, S Nakamura
The costs and benefits of polyandry are still not well understood. We studied the effects of multiple mating on the reproductive performance of female Brontispa longissima (Coleoptera: Chrysomelidae), one of the most serious pests of the coconut palm, by using three experimental treatments: (1) singly-mated females (single treatment); (2) females that mated 10 times with the same male (repetition treatment); and (3) females that mated once with each of 10 different males (polyandry treatment). Both multiple mating treatments resulted in significantly greater total egg production and the proportion of eggs that successfully hatched (hatching success) than with the single mating treatment...
August 30, 2016: Bulletin of Entomological Research
Miguel Hugo Kottow Lang
The worldwide scarcity of cadaveric organs for transplants is on the rise, due in part to extended medical indications and longevity of chronic patients with organic insufficiencies. Chile has an extremely low donor rate of 6.7 per million. Although consent is presumed by law, and recently amended to include a “reciprocity principle”, nearly four million persons have expressed in writing their unwillingness to donate and, of those remaining, 53% of families have rejected donating the organs of their deceased...
2016: Medwave
Rita Ostan, Daniela Monti, Paola Gueresi, Mauro Bussolotto, Claudio Franceschi, Giovannella Baggio
Data showing a remarkable gender difference in life expectancy and mortality, including survival to extreme age, are reviewed starting from clinical and demographic data and stressing the importance of a comprehensive historical perspective and a gene-environment/lifestyle interaction. Gender difference regarding prevalence and incidence of the most important age-related diseases, such as cardiovascular and neurodegenerative diseases, cancer, Type 2 diabetes, disability, autoimmunity and infections, are reviewed and updated with particular attention to the role of the immune system and immunosenescence...
October 1, 2016: Clinical Science (1979-)
Joelle H Fong, Jun Feng
This study examined patterns of onset of activity of daily living (ADL) disability in a nationally representative sample of older adults in mainland China. Using longitudinal data from the Chinese Longitudinal Healthy Longevity Survey from 1998 to 2008 (N = 5,570), nonparametric methods were used to evaluate median age at onset of various ADL disabilities and differences in the incidence of disabilities according to sex. The sampled older Chinese adults developed ADL disabilities, on average, between the ages of 89 and 94...
September 2016: Journal of the American Geriatrics Society
N Bezemer, S L Krauss, R D Phillips, D G Roberts, S D Hopper
Optimal foraging behaviour by nectavores is expected to result in a leptokurtic pollen dispersal distribution and predominantly near-neighbour mating. However, complex social interactions among nectarivorous birds may result in different mating patterns to those typically observed in insect-pollinated plants. Mating system, realised pollen dispersal and spatial genetic structure were examined in the bird-pollinated Eucalyptus caesia, a species characterised by small, geographically disjunct populations. Nine microsatellite markers were used to genotype an entire adult stand and 181 seeds from 28 capsules collected from 6 trees...
August 17, 2016: Heredity
Maíra Trevisan, Sergio A De Bortoli, Alessandra M Vacari, Valéria L Laurentis, Dagmara G Ramalho
Although the parasitoid Cotesia flavipes (Cameron) has proven effective in controlling sugarcane borer Diatraea saccharalis (Fabricius) for many years, concern has arisen over the quality of individuals produced at large scales. The parasitoid has been reared in laboratories in Brazil for more than 40 years, with no new introductions of new populations during that period. Since the quality of the parasitoids was not verified at the time of the species' introduction in Brazil, we do not know if there has been any reduction in quality so far...
2016: PloS One
Mohannad Ismail, Margot Brooks
Adaptation to temperature changes is vital to reduce adverse effects on individuals, and some may present phenotypic changes, which might be accompanied with physiological costs in fitness traits. The objective of this study was to determine whether the two strains of the herbivore Eccritotarsus catarinensis, a biological control agent against water hyacinth in South Africa, differ in their responses to temperature according to their geographical origin. We experimentally quantified the responses of the two strains, at three constant temperatures: 20°C, 25°C and 30°C, using laboratory cultures that originated from Brazil and Peru, where climates differ...
August 2016: Journal of Thermal Biology
João Paulo M Santos, Rubens A da Silva, Marcos Tadeu P Fernandes, Regina Célia Poli-Frederico, Denis C Santos, Rodrigo A C Andraus, Thais Maria F Fernandes, Karen B P Fernandes
AIM: This study aimed to identify the category of severe functional impairment defined by the LEFS-Brazil questionnaire in accordance to Lequesne Algofunctional Index for elderly people with osteoarthritis. METHODS: This cross-sectional study enrolled 105 elderly subjects from the EELO (Study of Aging and Longevity) project conducted in Londrina (PR), with hip and/or knee osteoarthritis confirmed by radiographic assessment. The functional status of these individuals was assessed by the Lequesne Algofunctional Index and the LEFS-Brazil questionnaire...
July 12, 2016: Revista Brasileira de Reumatologia
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