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1.
Osteoporos Int ; 31(10): 2025-2035, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32500299

RESUMO

In middle-aged and older men, an 18-month multi-component exercise program improved spinal trabecular BMD, paraspinal, and psoas muscle cross-sectional area (CSA) but not visceral adipose tissue (VAT). However, changes in both muscle and VAT CSA were associated with changes in spinal BMD, independent of the exercise intervention. INTRODUCTION: In older men, we previously reported that a multi-component exercise program improved lumbar spine (LS) trabecular volumetric BMD (Tb.vBMD) compared with no exercise. This study aimed to investigate the following: (1) the effect of the exercise program on paraspinal and psoas (back) muscle CSA and VAT, and 2) if any exercise-related changes in muscle CSA and/or VAT were associated with changes in spinal BMD. METHODS: Men (n = 180) aged 50-79 years were randomized to an exercise or no-exercise group. Exercise involved high-intensity progressive resistance training (60-85% max) with weight-bearing impact exercise (3 days/week) for 18 months. Quantitative computed tomography was used to assess L1-L3 Tb.vBMD, paraspinal, and psoas muscle CSA and VAT. RESULTS: Exercise resulted in a 2.6% ((95% CI, 1.1, 4.1), P < 0.01) net gain in back muscle CSA, but no effect on VAT (-1.6% (95% CI, -7.3, 4.2)) relative to no exercise. Robust regression indicated that percentage changes in Tb.vBMD were positively associated with changes (expressed as z-scores) in back muscle CSA in both the exercise (beta (ß)-coefficient = 1.9, 95% CI 0.5, 3.2, P = 0.007) and no-exercise (ß = 2.6, 95% CI, 1.1, 4.1, P = 0.001) group, and negatively with the changes in VAT (ß = -2.0, 95% CI -3.3, -0.7, P = 0.003) in the exercise only group. There were no group differences in the slopes for the muscle-bone or VAT-bone relationships. Regression analysis (pooled data) revealed that back muscle CSA and VAT were independent predictors of the change in Tb.vBMD, explaining 14% of the variance. CONCLUSION: A multi-component exercise program in middle-aged and older men improved spinal BMD and back muscle size but not visceral fat. However, changes in back muscle size and VAT were associated with the changes in spinal BMD, independent of exercise. TRIAL REGISTRATION: ACTRN 12617001224314, 22/08/2017 retrospectively registered.


Assuntos
Músculos do Dorso , Densidade Óssea , Idoso , Exercício Físico , Terapia por Exercício , Humanos , Gordura Intra-Abdominal/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade
2.
Osteoporos Int ; 29(2): 287-303, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28971226

RESUMO

PURPOSE: Certain cancer treatments are associated with bone loss and increased fracture risk. Weight-bearing impact exercise, resistance training or the combination, are recommended to preserve or improve bone mineral density (BMD) inhealthy older adults, but their efficacy in cancer survivors is less well understood. The aim of this systematic review with meta-analysis of randomised control trials (RCT) was to review the evidence regarding the role of exercise to counteract cancer treatment-induced bone loss. METHODS: Four databases were searched systematically with 12 RCTs of at least 6-month duration investigating the effects of exercise on BMD compared to a control group in adult cancer survivors identified. RESULTS: Meta-analysis was completed using available data from six studies enrolling 814 participants, with lumbar spine, femoral neck and/or total hip BMD as the primary outcome measures. Overall, there was no significant benefit of exercise compared to controls on BMD at the lumbar spine (0.0071 g/cm , 95% CI -0.0002 to 0.0145, p = 0.057), femoral neck (0.0044 g/cm , 95% CI -0.0005 to 0.0093, p = 0.077), or total hip (0.0024 g/cm , 95% CI -0.0038 to 0.0086, p = 0.443). Subgroup analysis revealed a positive effect on lumbar spine BMD in three studies implementing a combined resistance and impact exercise intervention (0.015 g/cm , 95% CI 0.003 to 0.028, p = 0.019). CONCLUSIONS: From the evidence available, exercise may not be sufficient to improve bone health in cancer survivors, but given the heterogeneity in the participant characteristics and several exercise programs which may not have been designed to specifically optimise bone health, these findings should be interpreted with caution.


Assuntos
Densidade Óssea/fisiologia , Sobreviventes de Câncer , Exercício Físico/fisiologia , Adulto , Terapia por Exercício/métodos , Colo do Fêmur/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Neoplasias/fisiopatologia , Neoplasias/terapia , Osteoporose/etiologia , Osteoporose/fisiopatologia , Osteoporose/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
J Nutr Health Aging ; 27(1): 38-45, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36651485

RESUMO

BACKGROUND: In recent years, a potential beneficial role of Vitamin K in neuromuscular function has been recognised. However, the optimal dietary intake of Vitamin K to support muscle function in the context of falls prevention remains unknown. OBJECTIVE: To examine the relationship of dietary Vitamin K1 and K2 with muscle function and long-term injurious fall-related hospitalisations in older women. DESIGN: Cohort study. PARTICIPANTS: 1347 community-dwelling older Australian women ≥70 years. MEASUREMENTS: A new Australian Vitamin K nutrient database, supplemented with published data, was used to calculate Vitamin K1 and K2 intake from a validated food frequency questionnaire at baseline (1998). Muscle function (grip strength and timed-up-and-go; TUG) as well plasma Vitamin D status (25OHD) were also assessed at baseline. Fall-related hospitalisations over 14.5 years were obtained from linked health records. Multivariable-adjusted logistic regression and Cox-proportional hazard models were used to analyse the data. RESULTS: Over 14.5 years of follow-up (14,774 person-years), 535 (39.7%) women experienced a fall-related hospitalisation. Compared to women with the lowest Vitamin K1 intake (Quartile 1, median 49 µg/d), those with the highest intake (Quartile 4, median 120 µg/d) had 29% lower odds (OR 0.71 95%CI 0.52-0.97) for slow TUG performance (>10.2 s), and 26% lower relative hazards of a fall-related hospitalisation (HR 0.74 95%CI 0.59-0.93) after multivariable adjustment. These associations were non-linear and plateaued at moderate intakes of ~70-100 µg/d. There was no relation to grip strength. Vitamin K2 intakes were not associated with muscle function or falls. CONCLUSION: A higher habitual Vitamin K1 intake was associated with better physical function and lower long-term injurious falls risk in community-dwelling older women. In the context of musculoskeletal health, Vitamin K1 found abundantly in green leafy vegetables should be promoted.


Assuntos
Vida Independente , Vitamina K 1 , Humanos , Feminino , Idoso , Masculino , Estudos de Coortes , Austrália , Vitamina K
4.
J Nutr Health Aging ; 26(1): 96-102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35067710

RESUMO

OBJECTIVES: To evaluate the feasibility of using voice-controlled intelligent personal assistants (VIPAs) to remotely deliver and monitor an individually-tailored, home-based exercise program to older adults living independently and alone. DESIGN: 12-week, prospective single-arm feasibility study. SETTING: Community residences. PARTICIPANTS: 15 adults aged 60 to 89 years living alone. INTERVENTION: All participants were prescribed home-based muscle strengthening, weight-bearing impact and balance exercises, increasing from two to four 10-minute sessions per day over 12 weeks. Sessions were delivered using VIPAs (Amazon Alexa Echo Show 5; "Alexa") and a novel software program ("Buddy Link"). The program was individualized by an exercise physiologist based on participant voice responses to Alexa questions. MEASUREMENTS: Study outcomes were feasibility (rate of retention, adherence, and adverse events), usability (System Usability Scale) and changes to quality of life (European Quality of Life Scale), and lower-extremity function (30 second sit-to-stand test). RESULTS: All 15 participants (mean age, 70.3 years) completed the study (retention 100%). Mean adherence to the exercise program was 115% (i.e., collectively all participants were prescribed 8640 exercises but completed 9944 exercises) with no adverse events reported to be related to the intervention and usability scored as above average (75/100). Other outcomes did not significantly change across the 12-week follow-up (all P>0.05). CONCLUSIONS: In this feasibility study of community-dwelling older adults living alone, a home-based exercise program delivered and monitored remotely by an exercise physiologist using VIPAs was safe and feasible.


Assuntos
Vida Independente , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Terapia por Exercício , Estudos de Viabilidade , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
5.
Mol Phylogenet Evol ; 48(3): 838-49, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18619861

RESUMO

Originally resident in southeastern Europe, the codling moth (Cydia pomonella L.) (Tortricidae) has achieved a nearly global distribution, being one of the most successful pest insect species known today. As shown in our accompanying study, mitochondrial genetic markers suggest a Pleistocenic splitting of Cydia pomonella into two refugial clades which came into secondary contact after de-glaciation. The actual distribution pattern shows, however, that Central European codling moths have experienced a geographic splitting into many strains and locally adapted populations, which is not reflected by their mitochondrial haplotype distribution. We therefore have applied, in addition to mitochondrial markers, an approach with a higher resolution potential at the population level, based on the analysis of amplification fragment length polymorphisms (AFLPs). As shown in the present study, AFLP markers elucidate the genetic structure of codling moth strains and populations from different Central European apple orchard sites. While individual genetic diversity within codling moth strains and populations was small, a high degree of genetic differentiation was observed between the analyzed strains and populations, even at a small geographic scale. One of the main factors contributing to local differentiation may be limited gene flow among adjacent codling moth populations. In addition, microclimatic, ecological, and geographic constraints also may favour the splitting of Cydia pomonella into many local populations. Lastly, codling moths in Central European fruit orchards may experience considerable selective pressure due to pest control activities. As a consequence of all these selective forces, today in Central Europe we see a patchy distribution of many locally adapted codling moth populations, each of them having its own genetic fingerprint. Because of the complete absence of any correlation between insecticide resistance and geographic or genetic distances among populations, AFLP markers do not have a prognostic value for predicting an outbreak of pesticide resistance in the field. By combining mitochondrial genetic data and AFLP analysis it was possible, however, to track the recent evolutionary history of Cydia pomonella on three different time scales: from population splitting in Pleistocene, to interbreeding of mitochondrial haplotypes in Holocene, to human-aided complete intermixing and splitting into many locally adapted populations in very recent times. The case of Cydia pomonella is reminiscent of examples of sympatric speciation and another example of a human-induced globally successful pest species.


Assuntos
Mariposas/efeitos dos fármacos , Mariposas/genética , Animais , Europa (Continente) , Evolução Molecular , Feminino , Marcadores Genéticos , Variação Genética , Geografia , Humanos , Resistência a Inseticidas/efeitos dos fármacos , Resistência a Inseticidas/genética , Masculino , Mitocôndrias/genética , Filogenia , Análise de Sequência de DNA , Fatores Sexuais
6.
Mol Phylogenet Evol ; 48(3): 825-37, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18620870

RESUMO

The codling moth (Cydia pomonella L., Tortricidae, Lepidoptera) is an important pest of pome fruit with global distribution. It has adapted successfully to different habitats by forming various ecotypes and populations, often termed strains, which differ among each other in several morphological, developmental, and physiological features. Many strains of Cydia pomonella have developed resistance against a broad range of chemically different pesticides. Obviously, pesticide-resistant strains must have a genetic basis inherent to the gene pool of codling moth populations, and this deserves our particular attention. The primary intention of the present study was to contribute novel information regarding the evolutionary phylogeny and phylogeography of codling moth populations in Central Europe. In addition, we aimed at testing the hypothesis that differential biological traits and response patterns towards pesticides in codling moth populations may be reflected at a mitochondrial DNA level. In particular, we wanted to test if pesticide resistance in codling moths is associated repeatedly and independently with more than one mitochondrial haplotype. To this end, we analyzed mitochondrial DNA and constructed phylogenetic trees based on three mitochondrial genes: cytochrome oxidase I (COI), the A+T-rich region of the control region (CR), and the nicotinamide adenine dinucleotide dehydrogenase subunit 5 (ND5). The results indicate that Central European populations of Cydia pomonella are clearly divided in two ancient clades. As shown by means of a molecular clock approach, the splitting of the two clades can be dated to a time period between the lower and middle Pleistocene, about 1.29-0.20 million years ago. It is assumed that the cyclic changes of warm and cold periods during Pleistocene may have lead to the geographic separation of codling moth populations due to glaciation, giving rise to the formation of the two separate refugial clades, as already shown for many other European animal species. Due to their inclination towards developing novel detoxification gene variants, codling moth individuals from both clades independently and multifariously may have developed pesticide resistance, and this process may be ongoing. During their more recent evolutionary history, natural events such as the gradual disappearance of climate-specific geographic barriers, as well as human-aided dispersal in recent historic times, may have allowed codling moth haplotypes from the original clades to interbreed and completely merge again, creating a globally successful insect species with a gene pool capable of responding to novel selective challenges by rapid adaptation.


Assuntos
Haplótipos , Mitocôndrias/genética , Mariposas/genética , Animais , Evolução Biológica , DNA Mitocondrial/genética , Diflubenzuron/farmacologia , Europa (Continente) , Evolução Molecular , Marcadores Genéticos , Genótipo , Modelos Genéticos , Filogenia , Análise de Sequência de DNA
7.
Artigo em Inglês | MEDLINE | ID: mdl-20483205

RESUMO

The identification of pure indigenous fish from hybridised populations represents a key issue in fisheries management and conservation biology. In the present study an approach for selection of purebred marble trout (Salmo trutta marmoratus C.) individuals out of admixed populations was set up and assessed. In a first step, baseline data sets of pure marble trout and pure brown trout specimens based on twelve microsatellite loci were used to simulate five consecutive generations of admixture. The baseline and the resulting simulation data sets were then combined with data of a 'real' hybridised marble trout population to perform a single individual assignment test as implemented in STRUCTURE. By this procedure the assignment approach was calibrated and it was possible to compare admixture coefficients obtained for individuals from different populations. The ranking of individual admixture coefficients on a plot and comparison with simulated data revealed that the test population was composed of pure marble trout individuals, first generation hybrids between marble trout and brown trout, and hybrid backcross specimens between both groups. However, by defining a critical q-value of 0.1 and additionally integrating individual sequence data of the mtDNA control region, it was possible to indicate individuals, which could be selected for the establishment of a pure marble trout strain.

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