55 research outputs found

    Uncoupling of Satellite DNA and Centromeric Function in the Genus Equus

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    In a previous study, we showed that centromere repositioning, that is the shift along the chromosome of the centromeric function without DNA sequence rearrangement, has occurred frequently during the evolution of the genus Equus. In this work, the analysis of the chromosomal distribution of satellite tandem repeats in Equus caballus, E. asinus, E. grevyi, and E. burchelli highlighted two atypical features: 1) several centromeres, including the previously described evolutionary new centromeres (ENCs), seem to be devoid of satellite DNA, and 2) satellite repeats are often present at non-centromeric termini, probably corresponding to relics of ancestral now inactive centromeres. Immuno-FISH experiments using satellite DNA and antibodies against the kinetochore protein CENP-A demonstrated that satellite-less primary constrictions are actually endowed with centromeric function. The phylogenetic reconstruction of centromere repositioning events demonstrates that the acquisition of satellite DNA occurs after the formation of the centromere during evolution and that centromeres can function over millions of years and many generations without detectable satellite DNA. The rapidly evolving Equus species gave us the opportunity to identify different intermediate steps along the full maturation of ENCs

    Current anti-doping policy: a critical appraisal

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    BACKGROUND: Current anti-doping in competitive sports is advocated for reasons of fair-play and concern for the athlete's health. With the inception of the World Anti Doping Agency (WADA), anti-doping effort has been considerably intensified. Resources invested in anti-doping are rising steeply and increasingly involve public funding. Most of the effort concerns elite athletes with much less impact on amateur sports and the general public. DISCUSSION: We review this recent development of increasingly severe anti-doping control measures and find them based on questionable ethical grounds. The ethical foundation of the war on doping consists of largely unsubstantiated assumptions about fairness in sports and the concept of a "level playing field". Moreover, it relies on dubious claims about the protection of an athlete's health and the value of the essentialist view that sports achievements reflect natural capacities. In addition, costly antidoping efforts in elite competitive sports concern only a small fraction of the population. From a public health perspective this is problematic since the high prevalence of uncontrolled, medically unsupervised doping practiced in amateur sports and doping-like behaviour in the general population (substance use for performance enhancement outside sport) exposes greater numbers of people to potential harm. In addition, anti-doping has pushed doping and doping-like behaviour underground, thus fostering dangerous practices such as sharing needles for injection. Finally, we argue that the involvement of the medical profession in doping and anti-doping challenges the principles of non-maleficience and of privacy protection. As such, current anti-doping measures potentially introduce problems of greater impact than are solved, and place physicians working with athletes or in anti-doping settings in an ethically difficult position. In response, we argue on behalf of enhancement practices in sports within a framework of medical supervision. SUMMARY: Current anti-doping strategy is aimed at eradication of doping in elite sports by means of all-out repression, buttressed by a war-like ideology similar to the public discourse sustaining international efforts against illicit drugs. Rather than striving for eradication of doping in sports, which appears to be an unattainable goal, a more pragmatic approach aimed at controlled use and harm reduction may be a viable alternative to cope with doping and doping-like behaviour

    Barriers and facilitators to using NHS Direct: a qualitative study of ‘users’ and ‘non-users’

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    Background NHS Direct, introduced in 1998, has provided 24/7 telephone-based healthcare advice and information to the public in England and Wales. National studies have suggested variation in the uptake of this service amongst the UK¿s diverse population. This study provides the first exploration of the barriers and facilitators that impact upon the uptake of this service from the perspectives of both `users¿ and `non- users¿. Methods Focus groups were held with NHS Direct `users¿ (N?=?2) from Bedfordshire alongside `non-users¿ from Manchester (N?=?3) and Mendip, Somerset (N?=?4). Each focus group had between five to eight participants. A total of eighty one people aged between 21 and 94 years old (M: 58.90, SD: 22.70) took part in this research. Each focus group discussion lasted approximately 90 minutes and was audiotape-recorded with participants¿ permission. The recordings were transcribed verbatim. A framework approach was used to analyse the transcripts. Results The findings from this research uncovered a range of barriers and facilitators that impact upon the uptake of NHS Direct. `Non-users¿ were unaware of the range of services that NHS Direct provided. Furthermore, `non-users¿ highlighted a preference for face-to face communication, identifying a lack of confidence in discussing healthcare over the telephone. This was particularly evident among older people with cognitive difficulties. The cost to telephone a `0845¿ number from a mobile was also viewed to be a barrier to access NHS Direct, expressed more often by `non-users¿ from deprived communities. NHS Direct `users¿ identified that awareness, ease of use and convenience were facilitators which influenced their decision to use the service. Conclusions An understanding of the barriers and facilitators which impact on the access and uptake of telephone-based healthcare is essential to move patients towards the self-care model. This research has highlighted the need for telephone-based healthcare services to increase public awareness; through the delivery of more targeted advertising to promote the service provision availabl

    Pallidal stimulation: an alternative to pallidotomy?

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