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991.
Carlos A. Fermín-Martínez Alejandro Márquez-Salinas Enrique C. Guerra Lilian Zavala-Romero Neftali Eduardo Antonio-Villa Luisa Fernández-Chirino Eduardo Sandoval-Colin Daphne Abigail Barquera-Guevara Alejandro Campos Muñoz Arsenio Vargas-Vázquez César Daniel Paz-Cabrera Daniel Ramírez-García Luis Miguel Gutiérrez-Robledo Omar Yaxmehen Bello-Chavolla 《Aging cell》2023,22(1):e13756
Aging is believed to occur across multiple domains, one of which is body composition; however, attempts to integrate it into biological age (BA) have been limited. Here, we consider the sex-dependent role of anthropometry for the prediction of 10-year all-cause mortality using data from 18,794 NHANES participants to generate and validate a new BA metric. Our data-driven approach pointed to sex-specific contributors for BA estimation: WHtR, arm and thigh circumferences for men; weight, WHtR, thigh circumference, subscapular and triceps skinfolds for women. We used these measurements to generate AnthropoAge, which predicted all-cause mortality (AUROC 0.876, 95%CI 0.864–0.887) and cause-specific mortality independently of ethnicity, sex, and comorbidities; AnthropoAge was a better predictor than PhenoAge for cerebrovascular, Alzheimer, and COPD mortality. A metric of age acceleration was also derived and used to assess sexual dimorphisms linked to accelerated aging, where women had an increase in overall body mass plus an important subcutaneous to visceral fat redistribution, and men displayed a marked decrease in fat and muscle mass. Finally, we showed that consideration of multiple BA metrics may identify unique aging trajectories with increased mortality (HR for multidomain acceleration 2.43, 95%CI 2.25–2.62) and comorbidity profiles. A simplified version of AnthropoAge (S-AnthropoAge) was generated using only BMI and WHtR, all results were preserved using this metric. In conclusion, AnthropoAge is a useful proxy of BA that captures cause-specific mortality and sex dimorphisms in body composition, and it could be used for future multidomain assessments of aging to better characterize the heterogeneity of this phenomenon. 相似文献
992.
Elena Magenau John Clifton-Brown Catherine Parry Chris Ashman Danny Awty-Carroll Andrea Ferrarini Mislav Kontek Enrico Martani Stefano Amaducci Chris Davey Oene Dolstra Vanja Jurišić Jason Kam Luisa M. Trindade Iris Lewandowski Andreas Kiesel 《Global Change Biology Bioenergy》2023,15(5):559-574
Due to its versatility and storability, biomass is an important resource for renewable materials and energy. Miscanthus hybrids combine high yield potential, low input demand, tolerance of certain marginal land types and several ecosystem benefits. To date, miscanthus breeding has focussed on increasing yield potential by maximising radiation interception through: (1) selection for early emergence, (2) increasing the growth rate to reach canopy closure as fast as possible, and (3) delayed flowering and senescence. The objective of this study is to compare early season re-growth in miscanthus hybrids cultivated across Europe. Determination of differences in early canopy development on end-of-year yield traits is required to provide information for breeding decisions to improve future crop performance. For this purpose, a trial was planted with four miscanthus hybrids (two novel seed-based hybrids M. sinensis × sinensis [M sin × sin] and M. sacchariflorus × sinensis [M sac × sin], a novel rhizome-based M sac × sin and a standard Miscanthus × giganteus [M × g] clone) in the UK, Germany, Croatia and Italy, and was monitored in the third and fourth growing season. We determined differences between the hybrids in base temperature, frost sensitivity and emergence strategy. M × g and M sac × sin mainly emerged from belowground plant organs, producing fewer but thicker shoots at the beginning of the growing season but these shoots were susceptible to air frosts (determined by recording 0°C 2 m above ground surface). By contrast, M sin × sin emerged 10 days earlier, avoiding damage by late spring frosts and producing a high number of thinner shoots from aboveground shoots. Therefore, we recommend cultivating M sac × sin at locations with low risk and M sin × sin at locations with higher risk of late spring frosts. Selecting miscanthus hybrids that produce shoots throughout the vegetation period is an effective strategy to limit the risk of late frost damage and avoid reduction in yield from a shortened growing season. 相似文献
993.
The Km and Vmax values characterizing the reaction of baker's yeast iso-I-cytochrome c, whether tri-methylated or not at lysine residue 72, with crude preparations of cytochrome c peroxidase, cytochrome c oxidase and succinate cytochrome c oxidoreductase from Saccharomyces cerevisiae are similar. These results, as well as the redox potential values, the auto-oxidability parameters and the circular dichroism spectra, strongly suggest that the biological methylation of yeast cytochrome c does not alter its functional properties. The functional characteristics of baker's yeast iso-I-cytochrome c are similar to those of horse heart cytochrome c and yeast iso-2-cytochrome c. 相似文献
994.
Giorgio Trombetta Giancarlo Balboni Anna di Iasio Enrico Grazi 《Biochemical and biophysical research communications》1977,74(4):1297-1301
Aldolase from rabbit muscle covalently binds fructose 1,6 bisphosphate after reduction with NaBH4. The reaction is stereospecific since after acid hydrolysis of the protein only N6(2-deoxy-2-glucitol) L-lysine is isolated. It is suggested that the lysyl amino group of the active site reacts with the of the C-2 group of fructose bisphosphate. 相似文献
995.
996.
997.
Luis Catasús Guerra 《Folia Geobotanica》1981,16(4):439-440
A new endemic genus, the Aristopsis gen. nov., collected in sandy savannahs of Pinar del Río Province, Cuba, with two species is described. It is possible that it is phylogenetically related to Aristida L. 相似文献
998.
Enrico Bertoli Massimo Masserini Sandro Sonnino Riccardo Ghidoni Benvenuto Cestaro Guido Tettamanti 《生物化学与生物物理学报:生物膜》1981,647(2):196-202
The influence of different gangliosides (GM1, GD1a, GT1b) on the fluidity and surface dynamics of phosphatidylcholine small unilamellar vesicles was studied by electron paramagnetic resonance. 5-and 16-nitroxystearic acid, sounding respectively the region close to the surface and that close to the hydrophobic core of the vesicle, were employed as spin-label probes. The signals released by 5-nitroxystearic acid showed that the presence of gangliosides reduced the mobility of the hydrocarbon chains around the probe. The effect increased by increasing ganglioside concentration, and diminished from GM1 to GD1a and GT1b. The decrease of membrane fluidity was also monitored by the 16-nitroxystearic acid probe. On addition of Ca2+ the fluidity of ganglioside-containing vesicles (as signalled by the 5-nitroxystearic acid probe) promptly decreased, thereafter returning slowly to the original value. It is suggested that gangliosides cause strong side-side head group interactions on the bilayer surface -between ganglioside oligosaccharide chains and between ganglioside and phosphatidylcholine polar portions - which lead the lipid chains to assembly in a more rigid fashion. The influence of Ca2+ is interpreted as due to lateral phase separation in the vesicle membrane. This phenomenon can be related to the formation or stabilization of ganglioside clusters on the vesicle surface. 相似文献
999.
We report on a computer experiment in which, using Monte Carlo techniques, we considered a three-turn (30-base-pairs) B-DNA fragment as a solute and a set of 1200 water molecules and 60 sodium counterions (at a temperature of 300 K) as a solvent. From a statistical analysis of the Monte Carlo simulation (applied to the water molecules and counterions in the B-DNA field), we determined that the counterions themselves conform to two helical structures intertwined with the two strands. The strutures of the water molecules solvating both counterion helices and the two B-DNA strands are fully analyzed and described in detail. A model for base-pair recognition based on the above findings is proposed. Aspects of the unwinding mechanism are discussed. 相似文献
1000.
Susanna Lagorio Sonia Rossi Paolo Vecchia Marco De Santis Lucia Bastianini Michele Fusilli Alvaro Ferrucci Enrico Desideri Pietro Comba 《Bioelectromagnetics》1997,18(6):418-421
The mortality experience of a cohort of Italian plastic-ware workers exposed to radiofrequency (RF)-electromagnetic fields generated by dielectric heat sealers was investigated. Follow-up extended from 1962 to 1992. The standardised mortality ratio (SMR) analysis was restricted to 481 women workers, representing 78% of the total person-years at risk. Mortality from malignant neoplasms was slightly elevated, and increased risks of leukemia and accidents were detected. The all-cancer SMR was higher among women employed in the sealing department, where exposure to RF occurred, than in the whole cohort. This study raises interest in a possible association between exposure to RF radiation and cancer risk. However, the study power was very small, and the possible confounding effects of exposure to solvents and vinyl chloride monomer (VCM) could not be ruled out. The hypothesis of an increased risk of cancer after radiofrequency exposure should be further explored by means of analytical studies characterised by adequate power and more accurate exposure assessment. Bioelectromagnetics 18:418–421, 1997. © 1997 Wiley-Liss, Inc. 相似文献