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2.
Nutrients ; 13(9)2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34579067

RESUMEN

Twilight and low luminance levels are visually challenging environments for the elderly, especially when driving at night. Carotenoid rich diets are known to increase macular pigment optical density (MPOD), which in turn leads to an improvement in visual function. It is not known whether augmenting MPOD can lead to a decrease in vision related night driving difficulties. Additionally, it is unknown if carotenoid supplementation provides additional measurable benefits to one's useful field of view (UFOV) along with a decreased composite crash risk score. The aim of the study was to evaluate changes in night vision function and UFOV in individuals that took carotenoid vitamin supplements for a six-month period compared to a placebo group. METHODS: A prospective, randomized, double-blind, six-month trial of a 14 mg zeaxanthin/7 mg lutein-based supplement was carried out. Participants were randomized into active or placebo group (approx 2:1). RESULTS: n = 33 participants (26 males/7 females) participated with 93% capsule intake compliance in the supplemented group (n = 24) and placebo group (n = 9). MPOD (mean/standard error SE) in the active group increased in the Right eye from 0.35 density units (du)/0.04 SE to 0.41 du/0.05 SE; p < 0.001 and in the Left eye from 0.35 du/0.05 SE to 0.37 du, p > 0.05). The supplemented group showed significant improvements in contrast sensitivity with glare in both eyes with improvements in LogMAR scores of 0.147 and 0.149, respectively (p = 0.02 and 0.01, respectively), monocularly tested glare recovery time improved 2.76 and 2.54 s, respectively, (p = 0.008 and p = 0.02), and we also noted a decreased preferred luminance required to complete visual tasks (p = 0.02 and 0.03). Improvements in UFOV scores of divided attention (p < 0.001) and improved composite crash risk score (p = 0.004) were seen in the supplemented group. The placebo group remained unchanged. CONCLUSIONS: The NVC demonstrates that augmenting MPOD in individuals with difficulty in night vision showed measurable benefits in numerous visual functions that are important for night vision driving in this small sample RCT. Additionally, we observed an improvement in UFOV divided attention test scores and decreased composite risk scores.


Asunto(s)
Suplementos Dietéticos , Luteína/farmacología , Pigmento Macular/metabolismo , Visión Nocturna/efectos de los fármacos , Visión Ocular/efectos de los fármacos , Agudeza Visual/efectos de los fármacos , Zeaxantinas/farmacología , Accidentes de Tránsito/prevención & control , Anciano , Conducción de Automóvil , Método Doble Ciego , Femenino , Humanos , Mácula Lútea/efectos de los fármacos , Mácula Lútea/metabolismo , Degeneración Macular , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Pruebas del Campo Visual
3.
Evolution ; 66(7): 2204-15, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22759296

RESUMEN

Variation in chemical energy, that is food availability, is posited to cause variation in body size. However, examinations of the relationship are rare and primarily limited to amniotes and zooplankton. Moreover, the relationship between body size and chemical energy may be impacted by phylogenetic history, clade-specific ecology, and heterogeneity of chemical energy in space and time. Considerable work remains to both document patterns in body size over gradients in food availability and understanding the processes potentially generating them. Here, we examine the functional relationship between body size and chemical energy availability over a broad assortment of marine mollusks varying in habitat and mobility. We demonstrate that chemical energy availability is likely driving body size patterns across habitats. We find that lower food availability decreases size-based niche availability by setting hard constraints on maximum size and potentially on minimum size depending on clade-specific ecology. Conversely, higher food availability promotes greater niche availability and potentially promotes evolutionary innovation with regard to size. We posit based on these findings and previous work that increases in chemical energy are important to the diversification of Metazoans through size-mediated niche processes.


Asunto(s)
Bivalvos/fisiología , Carbono/metabolismo , Gastrópodos/fisiología , Animales , Bivalvos/clasificación , Tamaño Corporal , Canadá , Ecosistema , Ingestión de Energía , Gastrópodos/clasificación , Análisis de los Mínimos Cuadrados , Filogenia , Análisis de Regresión , Estados Unidos
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