Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 4 )

2019 ( 217 )

2018 ( 324 )

2017 ( 299 )

Custom range...

Search Results: 1 - 10 of 299582 matches for " Stuart J Semple "
All listed articles are free for downloading (OA Articles)
Page 1 /299582
Display every page Item
Statin therapy, myopathy and exercise--a case report
Stuart J Semple
Lipids in Health and Disease , 2012, DOI: 10.1186/1476-511x-11-40
Abstract: Reducing high cholesterol levels through pharmacotherapy is a key goal for patients with dyslipedemia. Despite the controversy surrounding statins they remain one of the most widely prescribed groups of lipid-lowering drugs simply because of their effectiveness [1]. Serious adverse side effects are rare, however, myopathy symptoms including fatigue, weakness, cramps and muscle pain are commonly reported by patients [2]. These symptoms may be exacerbated in patients who exercise [2] and be prevalent in as many as 75% of athletes who take the drug [3]. The underlying mechanism(s) responsible for the statin-induced myopathy is unclear, however there is evidence that statins may upregulate muscle cell apoptosis, inflammation and protein catabolism in response to eccentric exercise [4]. Whether or not 6 months of statin therapy induces skeletal muscle related changes such that indirect markers of muscle damage are exacerbated following 'normal' sessions that induce moderate muscle soreness, is yet to be established. Indeed some will argue that there are currently very few studies implicating inflammation as a factor that may exacerbate statin therapy induced complications [5].A 34 year old male (weight 63 kg; BMI 21.8 kg/m2) presented to his general practitioner (GP) for a routine medical check-up. The patient, a non-smoker, had no known/diagnosed chronic disease, injury or infection, was on no medication and was generally in good health. As a junior athlete the patient had participated competitively in endurance activities (cross-country, athletics, tri/duathlon) at provincial and national level, and for the last 13 years his motivation to engage in regular physical activity was driven by the health belief model. On average, his training over the last few years included 3 road running sessions per week (2 × 30-40 min during the week and 1 × 60-100 min on the weekend). These sessions were usually completed at moderate intensity with the odd session (1 out of every 4) bei
Evidence That Emotion Mediates Social Attention in Rhesus Macaques
Emily J. Bethell, Amanda Holmes, Ann MacLarnon, Stuart Semple
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0044387
Abstract: Background Recent work on non-human primates indicates that the allocation of social attention is mediated by characteristics of the attending animal, such as social status and genotype, as well as by the value of the target to which attention is directed. Studies of humans indicate that an individual’s emotion state also plays a crucial role in mediating their social attention; for example, individuals look for longer towards aggressive faces when they are feeling more anxious, and this bias leads to increased negative arousal and distraction from other ongoing tasks. To our knowledge, no studies have tested for an effect of emotion state on allocation of social attention in any non-human species. Methodology We presented captive adult male rhesus macaques with pairs of adult male conspecific face images - one with an aggressive expression, one with a neutral expression - and recorded gaze towards these images. Each animal was tested twice, once during a putatively stressful condition (i.e. following a veterinary health check), and once during a neutral (or potentially positive) condition (i.e. a period of environmental enrichment). Initial analyses revealed that behavioural indicators of anxiety and stress were significantly higher after the health check than during enrichment, indicating that the former caused a negative shift in emotional state. Principle Findings The macaques showed initial vigilance for aggressive faces across both conditions, but subsequent responses differed between conditions. Following the health check, initial vigilance was followed by rapid and sustained avoidance of aggressive faces. By contrast, during the period of enrichment, the macaques showed sustained attention towards the same aggressive faces. Conclusions/Significance These data provide, to our knowledge, the first evidence that shifts in emotion state mediate social attention towards and away from facial cues of emotion in a non-human animal. This work provides novel insights into the evolution of emotion-attention interactions in humans, and mechanisms of social behaviour in non-human primates, and may have important implications for understanding animal psychological wellbeing.
Matthew W. Rogers,Nauris Tamulevicius,Stuart J. Semple,Zarko Krkeljas
Journal of Sports Science and Medicine , 2012,
Abstract: The purpose of this study was to determine the efficacy of a home-based kinesthesia, balance and agility (KBA) exercise program to improve symptoms among persons age > 50 years with knee osteoarthritis (OA). Forty-four persons were randomly assigned to 8-weeks, 3 times per week KBA, resistance training (RT), KBA + RT, or Control. KBA utilized walking agility exercises and single-leg static and dynamic balancing. RT used elastic resistance bands for open chain lower extremity exercises. KBA + RT performed selected exercises from each technique. Control applied inert lotion daily. Outcomes included the OA specific WOMAC Index of Pain, Stiffness, and Physical Function (PF), community activity level, exercise self-efficacy, self-report knee stability, and 15m get up & go walk (GUG). Thirty-three participants [70.7 (SD 8.5) years] completed the trial. Analysis of variance comparing baseline, mid-point, and follow-up measures revealed significant (p < 0.05) improvements in WOMAC scores among KBA, RT, KBA + RT, and Control, with no differences between groups. However, Control WOMAC improvements peaked at mid- point, whereas improvement in the exercise conditions continued at 8-weeks. There were no significant changes in community activity level. Only Control improved exercise self-efficacy. Knee stability was improved in RT and Control. GUG improved in RT and KBA+RT. These results indicate that KBA, RT, or a combination of the two administered as home exercise programs are effective in improving symptoms and quality of life among persons with knee OA. Control results indicate a strong placebo effect in the short term. A combination of KBA and RT should be considered as part of the rehabilitation program, but KBA or RT alone may be appropriate for some patients. Studies with more statistical power are needed to confirm or refute these results. Patient presentation, preferences, costs, and convenience should be considered when choosing an exercise rehabilitation approach for persons with knee OA
Andrew J McKune,Stuart J Semple,Edith M Peters-Futre
Biology of Sport , 2012,
Abstract: While much research has recently been focussing on the chronic effects of overtraining, the acute damaging effects of individual eccentric exercise bouts on muscle remain of interest and underlie long-term training effects. Systemic markers of muscle damage are limited in terms of sensitivity and reliability. A clearer insight into the extent of the damage and mechanisms involved are being obtained from ultrastructural, functional and molecular examination of the muscle. There are currently indications that while the initial muscle damage may appear to have negative consequences in the short term, intense eccentric exercise appears to initiate a remodelling process and promote favourable adaptation of muscle following training, which has applications for promoting health, rehabilitation and sports performance.
Do Women's Voices Provide Cues of the Likelihood of Ovulation? The Importance of Sampling Regime
Julia Fischer, Stuart Semple, Gisela Fickenscher, Rebecca Jürgens, Eberhard Kruse, Michael Heistermann, Ofer Amir
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024490
Abstract: The human voice provides a rich source of information about individual attributes such as body size, developmental stability and emotional state. Moreover, there is evidence that female voice characteristics change across the menstrual cycle. A previous study reported that women speak with higher fundamental frequency (F0) in the high-fertility compared to the low-fertility phase. To gain further insights into the mechanisms underlying this variation in perceived attractiveness and the relationship between vocal quality and the timing of ovulation, we combined hormone measurements and acoustic analyses, to characterize voice changes on a day-to-day basis throughout the menstrual cycle. Voice characteristics were measured from free speech as well as sustained vowels. In addition, we asked men to rate vocal attractiveness from selected samples. The free speech samples revealed marginally significant variation in F0 with an increase prior to and a distinct drop during ovulation. Overall variation throughout the cycle, however, precluded unequivocal identification of the period with the highest conception risk. The analysis of vowel samples revealed a significant increase in degree of unvoiceness and noise-to-harmonic ratio during menstruation, possibly related to an increase in tissue water content. Neither estrogen nor progestogen levels predicted the observed changes in acoustic characteristics. The perceptual experiments revealed a preference by males for voice samples recorded during the pre-ovulatory period compared to other periods in the cycle. While overall we confirm earlier findings in that women speak with a higher and more variable fundamental frequency just prior to ovulation, the present study highlights the importance of taking the full range of variation into account before drawing conclusions about the value of these cues for the detection of ovulation.
The law of brevity in macaque vocal communication is not an artifact of analyzing mean call durations
Stuart Semple,Minna J. Hsu,Govindasamy Agoramoorthy,Ramon Ferrer-i-Cancho
Computer Science , 2012, DOI: 10.1080/09296174.2013.799917
Abstract: Words follow the law of brevity, i.e. more frequent words tend to be shorter. From a statistical point of view, this qualitative definition of the law states that word length and word frequency are negatively correlated. Here the recent finding of patterning consistent with the law of brevity in Formosan macaque vocal communication (Semple et al., 2010) is revisited. It is shown that the negative correlation between mean duration and frequency of use in the vocalizations of Formosan macaques is not an artifact of the use of a mean duration for each call type instead of the customary 'word' length of studies of the law in human language. The key point demonstrated is that the total duration of calls of a particular type increases with the number of calls of that type. The finding of the law of brevity in the vocalizations of these macaques therefore defies a trivial explanation.
Displacement Behaviour Is Associated with Reduced Stress Levels among Men but Not Women
Changiz Mohiyeddini, Stephanie Bauer, Stuart Semple
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0056355
Abstract: Sex differences in the ability to cope with stress may contribute to the higher prevalence of stress-related disorders among women compared to men. We recently provided evidence that displacement behaviour - activities such as scratching and face touching - represents an important strategy for coping with stressful situations: in a healthy population of men, displacement behaviour during a social stress test attenuated the relationship between anxiety experienced prior to this test, and the subsequent self-reported experience of stress. Here, we extend this work to look at physiological and cognitive (in addition to self-reported) measures of stress, and study both men and women in order to investigate whether sex moderates the link between displacement behaviour and the response to stress. In a healthy study population, we quantified displacement behaviour, heart rate and cognitive performance during the Trier Social Stress Test, and used self-report questionnaires to assess the experience of stress afterwards. Men engaged in displacement behaviour about twice as often as women, and subsequently reported lower levels of stress. Bivariate correlations revealed that for men, higher rates of displacement behaviour were associated with decreased self-reported stress, fewer mistakes in the cognitive task and a trend towards lower heart rate; no relationships between displacement behaviour and stress measures were found for women. Moreover, moderation analyses revealed that high rates of displacement behaviour were associated with lower stress levels in men but not in women, and that high displacement behaviour rates were associated with poorer cognitive performance in women, but not men. These results point to an important sex difference in coping strategies, and highlight new avenues for research into sex biases in stress-related disorders.
Recently published papers: Take your predictions with a drop of saline ... and breathe deeply before turning on your phone
David J Semple, Lui G Forni
Critical Care , 2004, DOI: 10.1186/cc2915
Abstract: He that would know what shall be must consider what has been.Thomas Fuller, MD, Gnomologia (1732)Scoring systems are beloved by some intensivists. They can provide a means by which patients may be compared between facilities, therefore enabling sensible trials to be conducted. They may also play a role in directing treatment plans for patients. However, the Holy Grail for many enthusiasts remains their potential use as prognostic tools among the critically ill in an attempt to predict the future. One would hope that clinical acumen also plays a role in determining treatment and the study by Rocker and coworkers [1] is somewhat reassuring in this respect. That prospective study, which included some 851 mechanically ventilated patients, was performed to evaluate the predictive ability of, and outcomes associated with, daily clinician estimates of a probability of intensive care unit (ICU) survival under 10%. The usual baseline characteristics were recorded, together with daily Acute Physiology and Chornic Health Evaluation II score and Multiple Organ Dysfunction Score. After morning ward rounds the attending physician and each bedside nurse were asked to predict the clinical probability of ICU survival as one of the following: under 10%, 10–40%, 41–60%, 61–90%, or over 90%.Just over 35% of the cohort died on the ICU. Of those patients deemed to have a greater than 10% chance of surviving ICU, 87.8% survived. Of those with an expected survival chance of under 10%, 29% did actually survive their ICU stay, although no data are given regarding whether they survived their hospital stay. The physicians tended to have a bleaker outlook than the nursing staff, but when both observations were combined this was, unsurprisingly, a more powerful predictor. Indeed, the clinical prediction was more powerful than illness severity, use of inotropes and vasopressors, or organ dysfunction. However, the group thought to have a poor outlook was also more likely to have some form of life
Predicting the Vulnerability of Great Apes to Disease: The Role of Superspreaders and Their Potential Vaccination
Charlotte Carne, Stuart Semple, Helen Morrogh-Bernard, Klaus Zuberbühler, Julia Lehmann
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0084642
Abstract: Disease is a major concern for the conservation of great apes, and one that is likely to become increasingly relevant as deforestation and the rise of ecotourism bring humans and apes into ever closer proximity. Consequently, it is imperative that preventative measures are explored to ensure that future epidemics do not wipe out the remaining populations of these animals. In this paper, social network analysis was used to investigate vulnerability to disease in a population of wild orang-utans and a community of wild chimpanzees. Potential ‘superspreaders’ of disease - individuals with disproportionately central positions in the community or population - were identified, and the efficacy of vaccinating these individuals assessed using simulations. Three resident female orang-utans were identified as potential superspreaders, and females and unflanged males were predicted to be more influential in disease spread than flanged males. By contrast, no superspreaders were identified in the chimpanzee network, although males were significantly more central than females. In both species, simulating the vaccination of the most central individuals in the network caused a greater reduction in potential disease pathways than removing random individuals, but this effect was considerably more pronounced for orang-utans. This suggests that targeted vaccinations would have a greater impact on reducing disease spread among orang-utans than chimpanzees. Overall, these results have important implications for orang-utan and chimpanzee conservation and highlight the role that certain individuals may play in the spread of disease and its prevention by vaccination.
The Risk of Disease to Great Apes: Simulating Disease Spread in Orang-Utan (Pongo pygmaeus wurmbii) and Chimpanzee (Pan troglodytes schweinfurthii) Association Networks
Charlotte Carne, Stuart Semple, Helen Morrogh-Bernard, Klaus Zuberbühler, Julia Lehmann
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0095039
Abstract: All great ape species are endangered, and infectious diseases are thought to pose a particular threat to their survival. As great ape species vary substantially in social organisation and gregariousness, there are likely to be differences in susceptibility to disease types and spread. Understanding the relation between social variables and disease is therefore crucial for implementing effective conservation measures. Here, we simulate the transmission of a range of diseases in a population of orang-utans in Sabangau Forest (Central Kalimantan) and a community of chimpanzees in Budongo Forest (Uganda), by systematically varying transmission likelihood and probability of subsequent recovery. Both species have fission-fusion social systems, but differ considerably in their level of gregariousness. We used long-term behavioural data to create networks of association patterns on which the spread of different diseases was simulated. We found that chimpanzees were generally far more susceptible to the spread of diseases than orang-utans. When simulating different diseases that varied widely in their probability of transmission and recovery, it was found that the chimpanzee community was widely and strongly affected, while in orang-utans even highly infectious diseases had limited spread. Furthermore, when comparing the observed association network with a mean-field network (equal contact probability between group members), we found no major difference in simulated disease spread, suggesting that patterns of social bonding in orang-utans are not an important determinant of susceptibility to disease. In chimpanzees, the predicted size of the epidemic was smaller on the actual association network than on the mean-field network, indicating that patterns of social bonding have important effects on susceptibility to disease. We conclude that social networks are a potentially powerful tool to model the risk of disease transmission in great apes, and that chimpanzees are particularly threatened by infectious disease outbreaks as a result of their social structure.
Page 1 /299582
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.