Transregional linkages in the North-Eastern Atlantic - An ‘end-to-end ’ analysis of pelagic ecosystems

This review examines interregional linkages and gives an overview perspective on marine ecosystem functioning in the north-eastern Atlantic. It is based on three of the 'systems' considered by the European Network of Excellence for Ocean Ecosystems Analysis (EUR-OC EANS was established in 2004 under the European Framework VI funding programme to promote integration of marine ecological research within Europe), the Arctic and Nordic Seas, North Atlantic shelf seas and North Atlantic. The three systems share common open boundaries and the transport of water, heat, nutrients and particulates across these boundaries modifies local processes. Consistent with the EUR-OC EANS concept of 'end-to-end' analyses of marine food webs, the review takes an integrated approach linking ocean physics, lower trophic levels and working up the food web to top predators such as marine mammals. We begin with an overview of the regions focusing on the major physical patterns and their implications for the microbial community, phytoplankton, zooplankton, fish and top predators. Human-induced links between the regional systems are then considered and finally possible changes in the regional linkages over the next century are discussed. Because of the scale of potential impacts of climate change, this issue is considered in a separate section. The review demonstrates that the functioning of the ecosystems in each of the regions cannot be considered in isolation and the role of the atmosphere and ocean currents in linking the North Atlantic Ocean, North Atlantic shelf seas and the Arctic and Nordic Seas must be taken into account. Studying the North Atlantic and associated shelf seas as an integrated 'basin-scale' system will be a key challenge for the early twenty-first century. This requires a multinational approach that should lead to improved ecosystem-based approaches to conservation of natural resources, the maintenance of biodiversity, and a better understanding of the key role of the north-eastern Atlantic in the global carbon cycle.

Advanced glycation end product (AGE) accumulation on Bruch's membrane: links to age-related RPE dysfunction.

PURPOSE: Advanced glycation end products (AGEs) accumulate during aging and have been observed in postmortem eyes within the retinal pigment epithelium (RPE), Bruch's membrane, and subcellular deposits (drusen). AGEs have been associated with age-related dysfunction of the RPE-in particular with development and progression to age-related macular degeneration (AMD). In the present study the impact of AGEs at the RPE-Bruch's membrane interface was evaluated, to establish how these modifications may contribute to age-related disease. METHODS: AGEs on Bruch's membrane were evaluated using immunohistochemistry. A clinically relevant in vitro model of substrate AGE accumulation was established to mimic Bruch's membrane ageing. Responses of ARPE-19 growing on AGE-modified basement membrane (AGE-BM) for 1 month were investigated by using a microarray approach and validated by quantitative (q)RT-PCR. In addition to identified AGE-related mRNA alterations, lysosomal enzyme activity and lipofuscin accumulation were also studied in ARPE-19 grown on AGE-BM. RESULTS: Autofluorescent and glycolaldehyde-derived AGEs were observed in clinical specimens on Bruch's membrane and choroidal extracellular matrix. In vitro analysis identified a range of dysregulated mRNAs in ARPE-19 exposed to AGE-BM. Altered ARPE-19 degradative enzyme mRNA expression was observed on exposure to AGE-BM. AGE-BM caused a significant reduction in cathepsin-D activity in ARPE-19 (P

Müller glial dysfunction during diabetic retinopathy in rats is linked to accumulation of advanced glycation end-products and advanced lipoxidation end-products.

Aims/hypothesis: The impact of AGEs and advanced lipoxidation end-products (ALEs) on neuronal and Müller glial dysfunction in the diabetic retina is not well understood. We therefore sought to identify dysfunction of the retinal Müller glia during diabetes and to determine whether inhibition of AGEs/ALEs can prevent it.

Methods: Sprague-Dawley rats were divided into three groups: (1) non-diabetic; (2) untreated streptozotocin-induced diabetic; and (3) diabetic treated with the AGE/ALE inhibitor pyridoxamine for the duration of diabetes. Rats were killed and their retinas were evaluated for neuroglial pathology. Results: AGEs and ALEs accumulated at higher levels in diabetic retinas than in controls (p<0.001). AGE/ALE immunoreactivity was significantly diminished by pyridoxamine treatment of diabetic rats. Diabetes was also associated with the up-regulation of the oxidative stress marker haemoxygenase-1 and the induction of glial fibrillary acidic protein production in Müller glia (p<0.001). Pyridoxamine treatment of diabetic rats had a significant beneficial effect on both variables (p<0.001). Diabetes also significantly altered the normal localisation of the potassium inwardly rectifying channel Kir4.1 and the water channel aquaporin 4 to the Müller glia end-feet interacting with retinal capillaries. These abnormalities were prevented by pyridoxamine treatment.

Conclusions/interpretation: While it is established that AGE/ALE formation in the retina during diabetes is linked to microvascular dysfunction, this study suggests that these pathogenic adducts also play a role in Müller glial dysfunction.

'Murder or Mercy?' an innovative module helping UK medical students to articulate their own ethical standpoints regarding end-of-life decisions

Objectives This student selected component (SSC) was designed to equip United Kingdom (UK) medical students to respond ethically and with sensitivity to requests they might receive as qualified doctors in regard to euthanasia and assisted dying. The aim was to expose students to relevant opinions and experiences and to provide opportunities to explore and justify their own views and rehearse ethical decision making in a safe learning environment. Method The module is delivered by specialists from a number of disciplines including law, theology, medicine and nursing, each providing students with a working knowledge allowing them to actively discuss cases, articulate their own views and practise ethical reasoning through group and individual study. Visits to local intensive care units, palliative care wards and hospices are integrated effectively with theory. Student assessment comprises a dissertation, student-led debate and reflective commentary. Module impact was evaluated by analysis of student coursework and a questionnaire. Results Students found the content stimulating and relevant to their future career and agreed that the module was well-structured and that learning outcomes were achieved. They greatly appreciated the clinical context provided by the visits and opportunities to apply ethical reasoning to real cases and to debate ethical issues with peers. Students reported an increased discernment of the ethical and legal position and practical considerations and a greater awareness of the range of professional and lay viewpoints held. Student perceptions were confirmed on analysis of their submitted coursework. Many participants were less strongly in favour of euthanasia and assisted dying on module completion than at the outset but all felt better equipped to justify their own viewpoint and to respond appropriately to patient requests. Conclusions The multi-disciplinary nature of this course is helpful in preparing students to deal effectively and sensitively with ethical dilemmas they will encounter in their medical career. Use of an integrated, learner-centred approach equips students to actively engage with their peers in discussion of such issues and to formulate and defend their own position.

Canada's Compassionate Care Benefit:Is it an adequate public health response to addressing the issue of caregiver burden in end-of-life care?

Background: An increasingly significant public health issue in Canada, and elsewhere throughout the developed world, pertains to the provision of adequate palliative/end-of-life (P/EOL) care. Informal caregivers who take on the responsibility of providing P/EOL care often experience negative physical, mental, emotional, social and economic consequences. In this article, we specifically examine how Canada's Compassionate Care Benefit (CCB) - a contributory benefits social program aimed at informal P/EOL caregivers - operates as a public health response in sustaining informal caregivers providing P/EOL care, and whether or not it adequately addresses known aspects of caregiver burden that are addressed within the population health promotion (PHP) model. Methods. As part of a national evaluation of Canada's Compassionate Care Benefit, 57 telephone interviews were conducted with Canadian informal P/EOL caregivers in 5 different provinces, pertaining to the strengths and weaknesses of the CCB and the general caregiving experience. Interview data was coded with Nvivo software and emerging themes were identified by the research team, with such findings published elsewhere. The purpose of the present analysis was identified after comparing the findings to the literature specific to caregiver burden and public health, after which data was analyzed using the PHP model as a guiding framework. Results: Informal caregivers spoke to several of the determinants of health outlined in the PHP model that are implicated in their burden experience: gender, income and social status, working conditions, health and social services, social support network, and personal health practises and coping strategies. They recognized the need for improving the CCB to better address these determinants. Conclusions: This study, from the perspective of family caregivers, demonstrates that the CCB is not living up to its full potential in sustaining informal P/EOL caregivers. Effort is required to transform the CCB so that it may fulfill the potential it holds for serving as one public health response to caregiver burden that forms part of a healthy public policy that addresses the determinants of this burden. © 2011 Williams et al; licensee BioMed Central Ltd.

Enhancing family physician capacity to deliver quality palliative home care:An end-of-life, shared-care model

PROBLEM BEING ADDRESSED: Family physicians face innumerable challenges to delivering quality palliative home care to meet the complex needs of end-of-life patients and their families. OBJECTIVE OF PROGRAM: To implement a model of shared care to enhance family physicians' ability to deliver quality palliative home care, particularly in a community-based setting. PROGRAM DESCRIPTION: Family physicians in 3 group practices (N = 21) in Ontario's Niagara West region collaborated with an interprofessional palliative care team (including a palliative care advanced practice nurse, a palliative medicine physician, a bereavement counselor, a psychosocial-spiritual advisor, and a case manager) in a shared-care partnership to provide comprehensive palliative home care. Key features of the program included systematic and timely identification of end-of-life patients, needs assessments, symptom and psychosocial support interventions, regular communication between team members, and coordinated care guided by outcome-based assessment in the home. In addition, educational initiatives were provided to enhance family physicians' knowledge and skills. CONCLUSION: Because of the program, participants reported improved communication, effective interprofessional collaboration, and the capacity to deliver palliative home care, 24 hours a day, 7 days a week, to end-of-life patients in the community.

Educating families about end-of-life care in advanced dementia:Acceptability of a Canadian family booklet to nurses from Canada, France, and Japan

Background: The families of people with late-stage dementia need to be informed about the course of the dementia and the comfort/ palliative care option. A booklet was written for that purpose and can be provided to family members by physicians and nurses. Methods: The acceptability of the booklet for nurses was tested in Canada (French and English version), France (French Canadian version) and Japan (translated and adapted version). Results: Overall, 188 nurses completed a survey questionnaire. The booklet was accepted best in Canada and less so in France and Japan. Despite regional variation, the majority of the nurses perceived the booklet as useful for families. The French and Japanese nurses also reported a greater need for palliative care education in advanced dementia. Conclusion: The booklet may help nurses educate families about end-of-life issues in dementia palliative care, but local adaptation of the booklet content and physician engagement are necessary.