Effectiveness of a Lifestyle Physical Activity Versus a Structured Exercise Intervention in Older Adults
JOURNAL OF AGING AND PHYSICAL ACTIVITY
Authors: Van Roie, Evelien; Delecluse, Christophe; Opdenacker, Joke; De Bock, Katrien; Kennis, Eva; Boen, Filip
Abstract
Two groups of sedentary older adults, participating in either a lifestyle physical activity intervention (LIFE, n = 60) or a structured exercise intervention (STRU, n = 60), were compared with a control group (CO, n = 66) in terms of physical fitness and cardiovascular risk factors. Participants in LIFE were stimulated to integrate physical activity into their daily routines and received an individualized home-based program. Participants in STRU completed 5 supervised training sessions every 2 wk in a fitness center. Both interventions lasted 11 months and focused on endurance, strength, flexibility, and postural/balance exercises. The results revealed that the interventions were equally effective in improving functional performance. STRU was more effective than LIFE in improving cardiorespiratory and muscular fitness. Limited effects emerged on cardiovascular risk, with STRU improving in total cholesterol and HDL. Consequently, interventions aiming at reducing cardiovascular risks among sedentary elderly should focus on long-term changes in physical activity behavior.
Identification of a mutarotase gene involved in D-galactose utilization in Aspergillus nidulans
FEMS MICROBIOLOGY LETTERS
Authors: Kulcsar, Laszlo; Flipphi, Michel; Jonas, Agota; Sandor, Erzsebet; Fekete, Erzsebet; Karaffa, Levente
Abstract
Aldose 1-epimerases or mutarotases (EC 5.1.3.3) are catalyzing the interconversion of alpha- and beta-anomers of hemiacetals of aldose sugars such as D-glucose and D-galactose, and are presumed to play an auxiliary role in carbohydrate metabolism as mutarotation occurs spontaneously in watery solutions. The first step in the Leloir pathway of D-galactose breakdown is preceded by accelerated conversion of beta-D-galactopyranose into the alpha-anomer, the substrate of the anomer-specific D-galactose 1-kinase. Here, we identified two putative aldose-1-epimerase genes (galmA and galmB) in the model organism Aspergillus nidulans, and characterized them upon generation of single- and double deletion mutant strains, as well as overexpressing mutants carrying multiple copies of either. Assaying cell-free extracts from the galmB single-and galm double mutants, we observed that the mutarotation hardly exceeded spontaneous anomer conversion, while galmB multicopy strains displayed higher activities than the wild type, increasing with the copy number. When grown on D-galactose in submerged cultures, biomass formation and D-galactose uptake rates in mutants lacking galmB were considerably reduced. None such effects were observed studying galmA deletion mutants, which consistently behave like the wild type. We conclude that GalmB is the physiologically relevant mutarotase for the utilization of D-galactose in A. nidulans.