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Initial impact of the COVID-19 pandemic on physical activity and sedentary behavior in hypertensive older adults: An accelerometer-based analysis.
Browne, RAV, Macêdo, GAD, Cabral, LLP, Oliveira, GTA, Vivas, A, Fontes, EB, Elsangedy, HM, Costa, EC
Experimental gerontology. 2020;:111121
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Abstract
BACKGROUND This study reports the accelerometer-based physical activity (PA) and sedentary behavior (SB) before and during the COVID-19 pandemic in hypertensive older adults. METHODS Thirty-five hypertensive older adults were included in this observational study. Accelerometer-based PA and SB measures were assessed before (January to March 2020) and during (June 2020) the COVID-19 pandemic. Linear mixed models were used to assess within-group changes in PA and SB measures, adjusted by accelerometer wear time. RESULTS Before COVID-19 pandemic participants presented: 5809 steps/day (SE = 366), 303.1 min/day (SE = 11.9) of light PA, 15.5 min/day (SE = 2.2) of moderate-vigorous PA, and 653.0 min/day (SE = 12.6) of SB. During COVID-19 pandemic there was a decrease in steps/day (β = -886 steps/day, SE = 361, p = 0.018), in moderate-vigorous PA (β = -2.8 min/day, SE = 2.4, p = 0.018), and a trend in light PA (β = -26.6 min/day, SE = 13.4, p = 0.053). In addition, SB increased during the COVID-19 pandemic (β = 29.6 min/day, SE = 13.4, p = 0.032). The magnitude of changes was greater on the weekend, mainly for steps/day (β = -1739 steps/day, SE = 424, p < 0.001) and the SB pattern (more time spent in bouts of ≥10 and 30 min, less breaks/day and breaks/h). CONCLUSIONS The COVID-19 pandemic may elicit unhealthy changes in movement behavior in hypertensive older adults. Lower PA, higher and more prolonged SB on the weekend are the main features of the behavioral changes.
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FACEHBI: A Prospective Study of Risk Factors, Biomarkers and Cognition in a Cohort of Individuals with Subjective Cognitive Decline. Study Rationale and Research Protocols.
Rodriguez-Gomez, O, Sanabria, A, Perez-Cordon, A, Sanchez-Ruiz, D, Abdelnour, C, Valero, S, Hernandez, I, Rosende-Roca, M, Mauleon, A, Vargas, L, et al
The journal of prevention of Alzheimer's disease. 2017;(2):100-108
Abstract
BACKGROUND Long-term longitudinal studies with multimodal biomarkers are needed to delve into the knowledge of preclinical AD. Subjective cognitive decline has been proposed as a risk factor for the development of cognitive impairment. Thus, including individuals with SCD in observational studies may be a cost-effective strategy to increase the prevalence of preclinical AD in the sample. OBJECTIVES To describe the rationale, research protocols and baseline characteristics of participants in the Fundació ACE Healthy Brain Initiative (FACEHBI). DESIGN FACEHBI is a clinical trial (EudraCT: 2014-000798-38) embedded within a long-term observational study of individuals with SCD. SETTING Participants have been recruited at the memory clinic of Fundació ACE (Barcelona) from two different sources: patients referred by a general practitioner and individuals from an Open House Initiative. PARTICIPANTS 200 individuals diagnosed with SCD with a strictly normal performance in a comprehensive neuropsychological battery. MEASUREMENTS Individuals will undergo an extensive neuropsychological protocol, risk factor assessment and a set of multimodal biomarkers including florbetaben PET, structural and functional MRI, diffusion tensor imaging, determination of amyloid species in plasma and neurophthalmologic assessment with optical coherence tomography. RESULTS Two hundred individuals have been recruited in 15 months. Mean age was 65.9 years; mean MMSE was 29.2 with a mean of 14.8 years of education. CONCLUSIONS FACEHBI is a long-term study of cognition, biomarkers and lifestyle that has been designed upon an innovative symptom-based approach using SCD as target population. It will shed light on the pathophysiology of preclinical AD and the role of SCD as a risk marker for the development of cognitive impairment.
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Significance of treated agrowaste residue and autochthonous inoculates (Arbuscular mycorrhizal fungi and Bacillus cereus) on bacterial community structure and phytoextraction to remediate soils contaminated with heavy metals.
Azcón, R, Medina, A, Roldán, A, Biró, B, Vivas, A
Chemosphere. 2009;(3):327-34
Abstract
In this study, we analyzed the impact of treatments such as Aspergillus niger-treated sugar beet waste (SB), PO4(3-) fertilization and autochthonous inoculants [arbuscular mycorrhizal (AM) fungi and Bacillus cereus], on the bacterial community structure in a soils contaminated with heavy metals as well as, the effectiveness on plant growth (Trifolium repens). The inoculation with AM fungi in SB amended soil, increased plant growth similarly to PO4(3-) addition, and both treatments matched in P acquisition but bacterial biodiversity estimated by denaturing gradient gel electrophoresis of amplified 16S rDNA sequences, was more stimulated by the presence of the AM fungus than by PO4(3-) fertilization. The SB amendment plus AM inoculation increased the microbial diversity by 233% and also changed (by 215%) the structure of the bacterial community. The microbial inoculants and amendment used favoured plant growth and the phytoextraction process and concomitantly modified bacterial community in the rhizosphere; thus they can be used for remediation. Therefore, the understanding of such microbial ecological aspects is important for phytoremediation and the recovery of contaminated soils.
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Effectiveness of autochthonous bacterium and mycorrhizal fungus on Trifolium growth, symbiotic development and soil enzymatic activities in Zn contaminated soil.
Vivas, A, Barea, JM, Biró, B, Azcón, R
Journal of applied microbiology. 2006;(3):587-98
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Abstract
AIMS: This study investigates how autochthonous micro-organisms [bacterium and/or arbuscular mycorrhizal (AM) fungi] affected plant tolerance to Zn contamination. METHODS AND RESULTS Zinc-adapted and -nonadapted Glomus mosseae strains protected the host plant against the detrimental effect of Zn (600 microg g(-1)). Zn-adapted bacteria increased root growth and N, P nutrition in plants colonized by adapted G. mosseae and decreased the specific absorption rate (SAR) of Cd, Cu, Mo or Fe in plants colonized by Zn-nonadapted G. mosseae. Symbiotic structures (nodule number and extraradical mycelium) were best developed in plants colonized by those Zn-adapted isolates that were the most effective in increasing plant Zn tolerance. The bacterium also increased the quantity and quality (metabolic characteristics) of mycorrhizal colonization, with the highest improvement for arbuscular vitality and activity. Inocula also enhanced soil enzymatic activities (dehydrogenase, beta-glucosidase and phosphatase) and indol acetic acid (IAA) accumulation, particularly in the rhizosphere of plants inoculated with Zn-adapted isolates. CONCLUSIONS Glomus mosseae strains have a different inherent potential for improving plant growth and nutrition in Zn-contaminated soil. The bacterium increased the potential of mycorrhizal mycelium as inoculum. SIGNIFICANCE AND IMPACT OF THE STUDY Mycorrhizal performance, particularly that of the autochthonous strain, was increased by the bacterium and both contributed to better plant growth and establishment in Zn-contaminated soils.
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Interactive effect of Brevibacillus brevis and Glomus mosseae, both isolated from Cd contaminated soil, on plant growth, physiological mycorrhizal fungal characteristics and soil enzymatic activities in Cd polluted soil.
Vivas, A, Barea, JM, Azcón, R
Environmental pollution (Barking, Essex : 1987). 2005;(2):257-66
Abstract
The interaction between two autochthonous microorganisms (Brevibacillus brevis and Glomus mosseae) isolated from Cd amended soil increased plant growth, arbuscular mycorrhizal (AM) colonization and physiological characteristics of the AM infection (measured as SDH or ALP activities). The enhanced plant Cd tolerance after coinoculation with native microorganisms seemed to be a consequence of increased P and K acquisition and, simultaneously, of decreased concentration of Cd, Cr, Mn, Cu, Mo, Fe and Ni in plant tissue. Autochthonous microbial strains were more efficient for nutrient uptake, to immobilize metals and decrease their translocation to the shoot than reference G. mosseae (with or without bacteria). Indole acetic acid produced by B. brevis may be related to its ability for improving root growth, nodule production and AM fungal intra and extraradical development. Dehydrogenase, phosphatase and beta-glucosidase activities, indicative of microbial metabolism and soil fertility, were maximized by the coinoculation of autochthonous microorganisms in cadmium polluted conditions. As a consequence, the use of native microorganisms may result very efficient in bioremediation.
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Brevibacillus brevis isolated from cadmium- or zinc-contaminated soils improves in vitro spore germination and growth of Glomus mosseae under high Cd or Zn concentrations.
Vivas, A, Barea, JM, Azcón, R
Microbial ecology. 2005;(3):416-24
Abstract
In this study we investigated the saprophyte growth of two arbuscular-mycorrhizal fungi (Glomus mosseae isolate) under increasing Cd or Zn levels and the influence of a selected bacterial strain of Brevibacillus brevis. Microorganisms here assayed were isolated from Cd or Zn polluted soils. B. brevis increased the presymbiotic growth (germination rate growth and mycelial development) of Glomus mosseae. Spore germination and mycelial development of both G. mosseae isolate were reduced as much as the amount of Cd or Zn increased in the growth medium. In medium supplemented with 20 microg Cd mL(-1), the spore germination was only 12% after 20 days of incubation, but the coinoculation with B. brevis increased this value to 40% after only 15 days. The addition of 20 microg Cd mL(-1) to the growth medium drastically inhibited hyphal development, but the presence of the bacterium increased hyphal growth of G. mosseae from 195% (without Cd) until 254% (with 20 microg Cd mL(-1)). The corresponding bacterial effect increasing micelial growth ranged from 125% (without Zn) to 232% (200 microg Zn mL(-1)) in the case of G. mosseae isolated from Zn-polluted soil. Mycelial growth under 5 microg Cd mL(-1) (without bacterium) was similarly reduced from that produced at 15 microg Cd mL(-1) in the presence of the bacteria. As well, 50 microg Zn mL(-1) (without bacterium) reduced hyphal growth as much as 200 microg Zn mL(-1) did in the presence of B. brevis. The bacterial effect on the saprophytic growth of G. mosseae in absence of metal may be due to the involvement of indole acetic acid (IAA) produced by these bacteria. The Cd bioaccumulation ability exhibited (76%) by Cd-adapted B. brevis reduced the Cd damage on G. mosseae in Cd-contaminated medium. These capabilities of B. brevis isolates partially alleviate the inhibitory effects of Cd or Zn on the axenic growth of G. mosseae.
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Influence of a Bacillus sp. on physiological activities of two arbuscular mycorrhizal fungi and on plant responses to PEG-induced drought stress.
Vivas, A, Marulanda, A, Ruiz-Lozano, JM, Barea, JM, Azcón, R
Mycorrhiza. 2003;(5):249-56
Abstract
The effects of bacterial inoculation (Bacillus sp.) on the development and physiology of the symbiosis between lettuce and the arbuscular mycorrhizal (AM) fungi Glomus mosseae (Nicol. and Gerd.) Gerd. and Trappe and Glomus intraradices (Schenck and Smith) were investigated. Plant growth, mineral nutrition and gas-exchange values in response to bacterial inoculation after PEG-induced drought stress were also evaluated. In AM plants, inoculation with Bacillus sp. enhanced fungal development and metabolism, measured as succinate dehydrogenase (SDH) and alkaline phosphatase (ALP) activities, more than plant growth. Under non-stressed conditions, G. intraradices colonization increased all plant physiological values to a higher extent when in dual inoculation with the bacterium. Under stress conditions, the bacterium had an important stimulatory effect on G. intraradices development. Under such conditions, the effects of the bacterium on photosynthetic rate, water use efficiency (WUE) and stomatal conductance of lettuce plants differed with the fungus species. Plant-gas exchange was enhanced in G. intraradices- and reduced in G. mosseae-colonized plants when co-inoculated with Bacillus sp. Thus, the effects of each fungus on plant physiology were modulated by the bacterium. Stress was detrimental, particularly in G. intraradices-colonized plants without the bacterium, reducing intra and extraradical mycelium growth and vitality (SDH), as well as plant-gas exchange. Nevertheless, Bacillus sp. inoculation improved all these plant and fungal parameters to the same level as in non-stressed plants. The highest amount of alive and active AM mycelium for both fungi was obtained after co-inoculation with Bacillus sp. These results suggest that selected free-living bacteria and AM fungi should be co-inoculated to optimize the formation and functioning of the AM symbiosis in both normal and adverse environments.
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Influence of bacterial strains isolated from lead-polluted soil and their interactions with arbuscular mycorrhizae on the growth of Trifolium pratense L. under lead toxicity.
Vivas, A, Azcón, R, Biró, B, Barea, JM, Ruiz-Lozano, JM
Canadian journal of microbiology. 2003;(10):577-88
Abstract
We isolated two bacterial strains from an experimentally lead (Pb)-polluted soil in Hungary, 10 years after soil contamination. These strains represented the two most abundant cultivable bacterial groups in such soil, and we tested their influence on Trifolium pratense L. growth and on the functioning of native mycorrhizal fungi under Pb toxicity in a second Pb-spiked soil. Our results showed that bacterial strain A enhanced plant growth, nitrogen and phosphorus accumulations, nodule formation, and mycorrhizal infection, demonstrating its plant-growth-promoting activity. In addition, strain A decreased the amount of Pb absorbed by plants, when expressed on a root weight basis, because of increased root biomass due to the production of indoleacetic acid. The positive effect of strain A was not only evident after a single inoculation but also in dual inoculation with arbuscular mycorrhizal fungi. Strain A also exhibited higher tolerance than strain B when cultivated under increasing Pb levels in the spiked soil. Molecular identification unambiguously placed strain A within the genus Brevibacillus. We showed that it is important to select the most tolerant and efficient bacterial strain for co-inoculation with arbuscular mycorrhizal fungi to promote effective symbiosis and thus stimulate plant growth under adverse environmental conditions, such as heavy-metal contamination.
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Symbiotic efficiency of autochthonous arbuscular mycorrhizal fungus (G. mosseae) and Brevibacillus sp. isolated from cadmium polluted soil under increasing cadmium levels.
Vivas, A, Vörös, I, Biró, B, Campos, E, Barea, JM, Azcón, R
Environmental pollution (Barking, Essex : 1987). 2003;(2):179-89
Abstract
The effect of inoculation with indigenous naturally occurring microorganisms (an arbuscular mycorrhizal (AM) fungus and rhizosphere bacteria) isolated from a Cd polluted soil was assayed on Trifolium repens growing in soil contaminated with a range of Cd. One of the bacterial isolate showed a marked PGPR effect and was identified as a Brevibacillus sp. Mycorrhizal colonization also enhanced Trifolium growth and N, P, Zn and Ni content and the dually inoculated (AM fungus plus Brevibacillus sp.) plants achieved further growth and nutrition and less Cd concentration, particularly at the highest Cd level. Increasing Cd level in the soil decreased Zn and Pb shoot accumulation. Coinoculation of Brevibacillus sp. and AM fungus increased shoot biomass over single mycorrhizal plants by 18% (at 13.6 mg Cd kg(-1)), 26% (at 33.0 mg Cd kg(-1)) and 35% (at 85.1 mg Cd (kg(1)). In contrast, Cd transfer from soil to plants was substantially reduced and at the highest Cd level Brevibacillus sp. lowered this value by 37.5% in AM plants. Increasing Cd level highly reduced plant mycorrhization and nodulation. Strong positive effect of the bacterium on inocula, are important in plant Cd tolerance and development in Cd polluted soils.