12 research outputs found
The relationship of telomere length to baseline corticosterone levels in nestlings of an altricial passerine bird in natural populations
ArtĂculo de publicaciĂłn ISIBackground: Environmental stressors increase the secretion of glucocorticoids that in turn can shorten telomeres via oxidative damage. Modification of telomere length, as a result of adversity faced early in life, can modify an individual's phenotype. Studies in captivity have suggested a relationship between glucocorticoids and telomere length in developing individuals, however less is known about that relationship in natural populations.
Methods: In order to evaluate the effect of early environmental stressors on telomere length in natural populations, we compared baseline corticosterone (CORT) levels and telomere length in nestlings of the same age. We collected blood samples for hormone assay and telomere determination from two geographically distinct populations of the Thorn-tailed Rayadito (Aphrastura spinicauda) that differed in brood size; nestlings body mass and primary productivity. Within each population we used path analysis to evaluate the relationship between brood size, body mass, baseline CORT and telomere length.
Results: Within each distinct population, path coefficients showed a positive relationship between brood size and baseline CORT and a strong and negative correlation between baseline CORT and telomere length. In general, nestlings that presented higher baseline CORT levels tended to present shorter telomeres. When comparing populations it was the low latitude population that presented higher levels of baseline CORT and shorter telomere length.
Conclusions: Taken together our results reveal the importance of the condition experienced early in life in affecting telomere length, and the relevance of integrative studies carried out in natural conditions.FONDECYT Grant
11130245
FONDECYT
1140548
USA National Science Foundation Grant
IOS-0750540
ICM-005-002
PFB-23-CONICY
Photoresponsive passive micromixers based on spiropyran size-tunable hydrogels
\u3cp\u3eMicrofluidic devices allow the manipulation of fluids down to the micrometer scale and are receiving a lot of attention for applications where low volumes and high throughputs are required. In these micro channels, laminar flow usually dominates, which requires long residence times of the fluids, limiting the flow speed and throughput. Here a switchable passive mixer has been developed to control mixing and to easily clean microchannels. The mixer is based on a photoresponsive spiropyran based hydrogel of which the dimensions can be tuned by changing the intensity of the light. The size-tunable gels have been used to fabricate a passive slanted groove mixer that can be switched off by light allowing to change mixing of microfluidics to non-mixed flows. These findings open new possibilities for multi-purpose microfluidic devices where mixers and valves can be tuned by light. (Figure presented.).\u3c/p\u3
Possible association of the TERT promoter polymorphisms rs2735940, rs7712562 and rs2853669 with diabetes mellitus in obese elderly Polish population: results from the national PolSenior study
Childhood Physical and Sexual Abuse History and Leukocyte Telomere Length among Women in Middle Adulthood
Different effects of accelerated development and enhanced growth on oxidative stress and telomere shortening in amphibian larvae
Assortative mating for telomere length and antioxidant capacity in barn swallows (Hirundo rustica)
Leukocyte telomere length and its relation to food and nutrient intake in an elderly population
Up-Regulation of leucocytes Genes Implicated in Telomere Dysfunction and Cellular Senescence Correlates with Depression and Anxiety Severity Scores
Free radicals – an evolutionary perspective
This chapter provides an evolutionary perspective on free radical biology. We first explain the concept of life history trade-offs and discuss how the need to manage oxidative stress in an optimal way may be an important mechanism driving the outcome of many of these trade-offs. We examine the different solutions that organisms have evolved to combat the damaging consequences of oxidative stress. We then examine the ways in which balancing investment in such defenses against the consequences of sustaining damage has influenced life history traits such in the context of growth, foraging, diet and activity patterns, sexual signaling, reproduction, and defense against infection