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61.
Matthew Maddocks Vanessa Halliday Alpna Chauhan Victoria Taylor Annmarie Nelson Cathy Sampson Anthony Byrne Gareth Griffiths Andrew Wilcock 《PloS one》2013,8(12)
Background
A reduced exercise capacity is associated with increased morbidity and mortality in patients with advanced non-small cell lung cancer (NSCLC). Therapeutic exercise can be beneficial and neuromuscular electrical stimulation (NMES) of the quadriceps muscles may represent a practical approach. The primary aim of this study was to determine the acceptability of NMES of the quadriceps to patients with NSCLC used alongside palliative chemotherapy. Secondary aims explored aspects of safety and efficacy of NMES in this setting.Methods
Patients with advanced NSCLC due to receive first-line palliative chemotherapy were randomized to usual care with or without NMES. They were asked to undertake 30 minute sessions of NMES, ideally daily, but as a minimum, three times weekly. For NMES to be considered acceptable, it was predetermined that ≥80% of patients should achieve this minimum level of adherence. Qualitative interviews were held with a subset of patients to explore factors influencing adherence. Safety was assessed according to the Common Terminology Criteria for Adverse Events. Quadriceps muscle strength, thigh lean mass, and physical activity level were assessed at baseline and after three cycles of chemotherapy.Results
49 patients (28 male, median (IQR) age 69 (64−75) years) participated. Of 30 randomized to NMES, 18 were eligible for the primary endpoint, of whom 9 (50% [90% CI, 29 to 71]) met the minimum level of adherence. Adherence was enhanced by incorporating sessions into a daily routine and hindered by undesirable effects of chemotherapy. There were no serious adverse events related to NMES, nor significant differences in quadriceps muscle strength, thigh lean mass or physical activity level between groups.Conclusions
NMES is not acceptable in this setting, nor was there a suggestion of benefit. The need remains to explore NMES in patients with cancer in other settings.Trial Registration
Current Controlled Trials ISRCTN 42944026 www.controlled-trials.com/ISRCTN42944026 相似文献62.
The Impact of Adult Vitamin D Deficiency on Behaviour and Brain Function in Male Sprague-Dawley Rats
Jacqueline H. Byrne Meggie Voogt Karly M. Turner Darryl W. Eyles John J. McGrath Thomas H. J. Burne 《PloS one》2013,8(8)
Background
Vitamin D deficiency is common in the adult population, and this has been linked to depression and cognitive outcomes in clinical populations. The aim of this study was to investigate the effects of adult vitamin D (AVD) deficiency on behavioural tasks of relevance to neuropsychiatric disorders in male Sprague-Dawley rats.Methods
Ten-week old male Sprague-Dawley rats were fed a control or vitamin D deficient diet for 6 weeks prior to, and during behavioural testing. We first examined a range of behavioural domains including locomotion, exploration, anxiety, social behaviour, learned helplessness, sensorimotor gating, and nociception. We then assessed locomotor response to the psychomimetic drugs, amphetamine and MK-801. Attention and vigilance were assessed using the 5 choice serial reaction time task (5C-SRT) and the 5 choice continuous performance task (5C-CPT) and, in a separate cohort, working memory was assessed using the delay match to sample (DMTS) task. We also examined excitatory and inhibitory neurotransmitters in prefrontal cortex and striatum.Results
AVD-deficient rats were deficient in vitamin D3 (<10 nM) and had normal calcium and phosphate levels after 8–10 weeks on the diet. Overall, AVD deficiency was not associated with an altered phenotype across the range of behavioural domains tested. On the 5C-SRT AVD-deficient rats made more premature responses and more head entries during longer inter-trial intervals (ITI) than control rats. On the 5C-CPT AVD-deficient rats took longer to make false alarm (FA) responses than control rats. AVD-deficient rats had increases in baseline GABA levels and the ratio of DOPAC/HVA within the striatum.Conclusions
AVD-deficient rats exhibited no major impairments in any of the behavioural domains tested. Impairments in premature responses in AVD-deficient rats may indicate that these animals have specific alterations in striatal systems governing compulsive or reward-seeking behaviour. 相似文献63.
R. D. O’Dea J. M. Osborne A. J. El Haj H. M. Byrne S. L. Waters 《Journal of mathematical biology》2013,67(5):1199-1225
In vitro tissue engineering is emerging as a potential tool to meet the high demand for replacement tissue, caused by the increased incidence of tissue degeneration and damage. A key challenge in this field is ensuring that the mechanical properties of the engineered tissue are appropriate for the in vivo environment. Achieving this goal will require detailed understanding of the interplay between cell proliferation, extracellular matrix (ECM) deposition and scaffold degradation. In this paper, we use a mathematical model (based upon a multiphase continuum framework) to investigate the interplay between tissue growth and scaffold degradation during tissue construct evolution in vitro. Our model accommodates a cell population and culture medium, modelled as viscous fluids, together with a porous scaffold and ECM deposited by the cells, represented as rigid porous materials. We focus on tissue growth within a perfusion bioreactor system, and investigate how the predicted tissue composition is altered under the influence of (1) differential interactions between cells and the supporting scaffold and their associated ECM, (2) scaffold degradation, and (3) mechanotransduction-regulated cell proliferation and ECM deposition. Numerical simulation of the model equations reveals that scaffold heterogeneity typical of that obtained from $\mu $ CT scans of tissue engineering scaffolds can lead to significant variation in the flow-induced mechanical stimuli experienced by cells seeded in the scaffold. This leads to strong heterogeneity in the deposition of ECM. Furthermore, preferential adherence of cells to the ECM in favour of the artificial scaffold appears to have no significant influence on the eventual construct composition; adherence of cells to these supporting structures does, however, lead to cell and ECM distributions which mimic and exaggerate the heterogeneity of the underlying scaffold. Such phenomena have important ramifications for the mechanical integrity of engineered tissue constructs and their suitability for implantation in vivo. 相似文献
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65.
Marie Dacke Marcus Byrne Jochen Smolka Eric Warrant Emily Baird 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2013,199(1):17-23
Upon locating a suitable dung pile, ball-rolling dung beetles shape a piece of dung into a ball and roll it away in a straight line. This guarantees that they will not return to the dung pile, where they risk having their ball stolen by other beetles. Dung beetles are known to use celestial compass cues such as the sun, the moon and the pattern of polarised light formed around these light sources to roll their balls of dung along straight paths. Here, we investigate whether terrestrial landmarks have any influence on straight-line orientation in dung beetles. We find that the removal or re-arrangement of landmarks has no effect on the beetle’s orientation precision. Celestial compass cues dominate straight-line orientation in dung beetles so strongly that, under heavily overcast conditions or when prevented from seeing the sky, the beetles can no longer orient along straight paths. To our knowledge, this is the only animal with a visual compass system that ignores the extra orientation precision that landmarks can offer. 相似文献
66.
Male-male competition is recognized as a potent force of sexual selection. When intra-sexual competition is strong then selection theory predicts that alternative male phenotypes will evolve. Circellium bacchus is a large, hornless, ball-rolling dung beetle with extensive variation in size and subject to intense male-male contest competition. We proposed that small male C. bacchus, which are unlikely to be successful in male contest competition, would adopt the alternative reproductive tactic of sneaking copulations. This alternative tactic is likely to influence not only behavior, but morphology with an expectation that sneaking males would invest more resources in testes development. Investigation of testis allometry revealed that smaller male C. bacchus beetles had relatively larger testes than their bigger conspecifics. Furthermore, as resources may be limited during larval development, differential investment in testes development should result in adult male beetles either competing for fertilizations or for access to mates. This is seen in C. bacchus as two alternate male phenotypes; smaller beetles with a relatively low body mass invest proportionately more in testes development compared to larger, heavier form in which testes size does not scale with condition. To our knowledge this study provides the first investigation of alternative phenotypes in the reproductive tactics of a ball-rolling dung beetle species. 相似文献
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69.
Sergio S. Barbosa Selma O. Klanten Jonathan B. Puritz Robert J. Toonen Maria Byrne 《Biological journal of the Linnean Society. Linnean Society of London》2013,108(4):821-833
The present study investigated the fine‐scale population genetic structure of sympatric asterinid sea stars with contrasting modes of larval development (benthic versus pelagic). Parvulastra exigua lacks a dispersive life phase yet is one of the worlds most widely distributed and abundant sea stars, whereas Meridiastra calcar, a sea star with a dispersive larva, has a more limited regional scale distribution. Populations of P. exigua sampled from tide pools on three adjacent headlands showed significant genetic substructure (mitochodrial DNA control region) at fine spatial scales (tide pools < 300 m apart: FST = 0.249, P < 0.01; headlands 5–15 km apart: FST = 0.125, P = 0.04). As expected, M. calcar populations sampled from the same headlands did not exhibit significant genetic structuring (FST = 0.029, P = 0.14). The life‐history traits of P. exigua, a mixed mating system (selfing + outcrossing), pseudocopulation among closely‐related conspecifics, and an entirely benthic life cycle with a philopatric larva, undoubtedly influence its strong genetic structure across fine spatial scales. Localized genetic structure, especially at the very fine‐scale of tide pools, would not be detected in the more typical regional scale approaches adopted by most studies of marine invertebrate populations. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, ●●, ●●–●●. 相似文献
70.