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Scientists at the University of Rochester pulled off a remarkable experiment: they transferred a longevity-related gene from the famously long-lived naked mole rat into mice, and the mice ended up healthier and lived longer。 The special gene boosts production of a substance called high molecular weight hyaluronic acid, which appears to protect agai
Root turnover is important to the global carbon budget as well as to nutrient cycling in ecosystems and to the success of individual plants. Our ability to predict the effects of environmental change on root turnover is limited by the difficulty of measuring root dynamics, but emerging evidence suggests that roots, like leaves, possess suites of interrelated traits that are linked to their life span. In graminoids, high tissue density has been linked to increased root longevity. Other studies have found root longevity to be positively correlated with mycorrhizal colonization and negatively correlated with nitrogen concentration, root maintenance respiration and specific root length. Among fruit trees, apple roots (which are of relatively small diameter, low tissue density and have little lignification of the exodermis) have much shorter life spans than the roots of citrus, which have opposite traits. Likewise, within the branched network of the fine root system, the finest roots with no daughter roots tend to have higher N concentrations, faster maintenance respiration, higher specific root length and shorter life spans than secondary and tertiary roots that bear daughter roots. Mycorrhizal colonization can enhance root longevity by diverse mechanisms, including enhanced tolerance of drying soil and enhanced defence against root pathogens. Many variables involved in building roots might affect root longevity, including root diameter, tissue density, N concentration, mycorrhizal fungal colonization and accumulation of secondary phenolic compounds. These root traits are highly plastic and are strongly affected by resource supply (CO 2 , N, P and water). Therefore the response of root longevity to altered resource availability associated with climate change can be estimated by considering how changes in resource availability affect root construction and physiology. A cost–benefit approach to predicting root longevity assumes that a plant maintains a root only until the efficiency of resource acquisition is maximized. Using an efficiency model, we show that reduced tissue Nconcentration and reduced root maintenance respiration, both of which are predicted to result from elevated CO 2 , should lead to slightly longer root life spans. Complex interactions with soil biota and shifts in plant defences against root herbivory and parasitism, which are not included in the present efficiency model, might alter the effects of future climate change on root longevity in unpredicted ways.
Human longevity is a complex phenotype with a significant familial component, yet little is known about its genetic antecedents. Increasing evidence from animal models suggests that the insulin/IGF-1 signaling (IIS) pathway is an important, evolutionarily conserved biological pathway that influences aging and longevity. However, to date human data have been scarce. Studies have been hampered by small sample sizes, lack of precise phenotyping, and population stratification, among other challenges. Therefore, to more precisely assess potential genetic contributions to human longevity from genes linked to IIS signaling, we chose a large, homogeneous, long-lived population of men well-characterized for aging phenotypes, and we performed a nested-case control study of 5 candidate longevity genes. Genetic variation within the FOXO3A gene was strongly associated with human longevity. The OR for homozygous minor vs. homozygous major alleles between the cases and controls was 2.75 (P = 0.00009; adjusted P = 0.00135). Long-lived men also presented several additional phenotypes linked to healthy aging, including lower prevalence of cancer and cardiovascular disease, better self-reported health, and high physical and cognitive function, despite significantly older ages than controls. Several of these aging phenotypes were associated with FOXO3A genotype. Long-lived men also exhibited several biological markers indicative of greater insulin sensitivity and this was associated with homozygosity for the FOXO3A GG genotype. Further exploration of the FOXO3A gene, human longevity and other aging phenotypes is warranted in other populations.
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This paper assesses inequality in longevity across education and gender groups in 23 OECD countries around 2011. Data on mortality rates by age, gender, educationals attainment and for, 17 countries, cause of death, were collected from national sources, with similar treatment applied to all countries in order to derive comparable measures of longevity at age 25 and 65 by gender and education. These estimates show that, on average, the gap in life expectancy between high and low-educationed people is 8 years for men and 5 years for women at age 25 years, and 3.5 years for men and 2.5 years for women at age 65. Other measures of inequalities in longevity by education (such as country averages of age-standardised mortality rates and the slope index of inequality) do not significantly change the inequality ranking of countries relative to one based on life expectancy measures. While significant, differences in longevity between groups with low and high educational attainment account, on average, for around 10% of overall differences in ages of death. Cardio-vascular diseases are the first cause of death for all gender and education groups after age 65 years, and the first cause of mortality inequality between the high and low-education elderly.
Oxidative Medicine and Cellular Longevity publishes research involving cellular and molecular mechanisms of oxidative stress in the nervous system and related organ systems in relation to aging, immune function, vascular biology, and metabolism.
Caloric restriction has been shown to increase longevity in organisms ranging from yeast to mammals. In some organisms, this has been associated with a decreased fat mass and alterations in insulin/insulin-like growth factor 1 (IGF-1) pathways. To further explore these associations with enhanced longevity, we studied mice with a fat-specific insulin receptor knockout (FIRKO). These animals have reduced fat mass and are protected against age-related obesity and its subsequent metabolic abnormalities, although their food intake is normal. Both male and female FIRKO mice were found to have an increase in mean life-span of approximately 134 days (18%), with parallel increases in median and maximum life-spans. Thus, a reduction of fat mass without caloric restriction can be associated with increased longevity in mice, possibly through effects on insulin signaling.
Hubble has revealed a giant planet-forming disk unlike anything astronomers have seen before。 Nicknamed “Dracula’s Chivito,” the enormous structure appears turbulent and oddly lopsided, with towering filaments visible on only one side。 The disk contains enough material to potentially create multiple giant planets, making it a fascinating new labora
Scientists may have found a powerful new way to hunt for alien life — not by searching for specific molecules, but by looking for hidden patterns in how those molecules are organized。 Researchers discovered that living systems leave behind a kind of chemical “fingerprint” in the statistical distribution of amino acids and fatty acids, one that cons
Astronomers have spotted something surprising in the far outer Solar System—a faint, short-lived atmosphere clinging to a tiny icy world that shouldn’t be able to hold one at all。 The object, called 2002 XV93, is far smaller than Pluto, yet observations during a rare stellar alignment revealed its presence through a subtle dimming of starlight。 Eve
Penn researchers have developed a smarter AI method for solving notoriously difficult inverse equations, which help scientists uncover hidden causes behind observable effects。 By introducing “mollifier layers” that smooth noisy data, they’ve made these calculations more stable and far less computationally demanding。 This could transform fields like
Scientists have pulled off a mind-bending quantum experiment that sounds almost impossible: they showed that tiny metal particles made of thousands of atoms can exist in multiple places at once。 Using advanced laser techniques, researchers at the University of Vienna observed quantum interference in sodium nanoparticles far larger than the kinds of
Physicists may have just cracked open a hidden side of the quantum world。 For decades, every known particle was thought to belong to one of two categories — bosons or fermions — but researchers have now shown that bizarre “in-between” particles called anyons could also exist in a one-dimensional system。 Even more exciting, these strange particles m
A major obstacle may be standing in the way of the next generation of ultra-tiny computer chips。 Researchers discovered that many promising 2D materials lose their advantages because an invisible atomic-scale gap forms when they are combined with insulating layers。 That tiny gap weakens electronic performance and could prevent further miniaturizati
A new quantum physics study reveals that simply changing a magnetic field over time can unlock entirely new forms of matter that don’t exist under normal conditions。 By carefully “driving” materials with timed magnetic shifts, researchers created exotic quantum states that could be far more stable and resistant to errors—one of the biggest challeng
A new study suggests AI chatbots may do more than spread misinformation — they can actively strengthen a user’s false beliefs。 Because conversational AI often validates and builds on what users say, it can make distorted memories, conspiracy theories, or delusions feel more believable and emotionally real。 Researchers warn that AI companions may be