The endothelial glycocalyx prefers albumin for evoking shear stress-induced, nitric oxide-mediated coronary dilatation

Background: Shear stress induces coronary dilatation via production of nitric oxide ( NO). This should involve the endothelial glycocalyx ( EG). A greater effect was expected of albumin versus hydroxyethyl starch ( HES) perfusion, because albumin seals coronary leaks more effectively than HES in an EG-dependent way. Methods: Isolated hearts ( guinea pigs) were perfused at constant pressure with Krebs-Henseleit buffer augmented with 1/3 volume 5% human albumin or 6% HES ( 200/0.5 or 450/0.7). Coronary flow was also determined after EG digestion ( heparinase) and with nitro-L-arginine ( NO-L-Ag). Results: Coronary flow ( 9.50 +/- 1.09, 5.10 +/- 0.49, 4.87 +/- 1.19 and 4.15 +/- 0.09 ml/ min/ g for `albumin', `HES 200', `HES 450' and `control', respectively, n = 5-6) did not correlate with perfusate viscosity ( 0.83, 1.02, 1.24 and 0.77 cP, respectively). NO-L-Ag and heparinase diminished dilatation by albumin, but not additively. Alone NO-L-Ag suppressed coronary flow during infusion of HES 450. Electron microscopy revealed a coronary EG of 300 nm, reduced to 20 nm after heparinase. Cultured endothelial cells possessed an EG of 20 nm to begin with. Conclusions: Albumin induces greater endothelial shear stress than HES, despite lower viscosity, provided the EG contains negative groups. HES 450 causes some NO-mediated dilatation via even a rudimentary EG. Cultured endothelial cells express only a rudimentary glycocalyx, limiting their usefulness as a model system. Copyright (c) 2007 S. Karger AG, Basel

The transition experience of rural older persons with advanced cancer and their families: a grounded theory study

BACKGROUND: Transitions often occur suddenly and can be traumatic to both patients with advanced disease and their families. The purpose of this study was to explore the transition experience of older rural persons with advanced cancer and their families from the perspective of palliative home care patients, bereaved family caregivers, and health care professionals. The specific aims were to: (1) describe the experience of significant transitions experienced by older rural persons who were receiving palliative home care and their families and (2) develop a substantive theory of transitions in this population. METHODS: Using a grounded theory approach, 27 open-ended individual audio-taped interviews were conducted with six older rural persons with advanced cancer and 10 bereaved family caregivers. Four focus group interviews were conducted with 12 palliative care health care professionals. All interviews were transcribed verbatim, coded, and analyzed using Charmaz\u27s constructivist grounded theory approach. RESULTS: Within a rural context of isolation, lack of information and limited accessibility to services, and values of individuality and community connectedness, older rural palliative patients and their families experienced multiple complex transitions in environment, roles/relationships, activities of daily living, and physical and mental health. Transitions disrupted the lives of palliative patients and their caregivers, resulting in distress and uncertainty. Rural palliative patients and their families adapted to transitions through the processes of Navigating Unknown Waters . This tentative theory includes processes of coming to terms with their situation, connecting, and redefining normal. Timely communication, provision of information and support networks facilitated the processes. CONCLUSION: The emerging theory provides a foundation for future research. Significant transitions identified in this study may serve as a focus for improving delivery of palliative and end of life care in rural areas. Improved understanding of the transitions experienced by advanced cancer palliative care patients and their families, as well as the psychological processes involved in adapting to the transitions, will help health care providers address the unique needs of this vulnerable population

A qualitative study of naturopathy in rural practice: A focus upon naturopaths' experiences and perceptions of rural patients and demands for their services

Background. Complementary and alternative medicine (CAM) use - of which naturopathy constitutes a significant proportion - accounts for approximately half of all health consultations and half of out-of-pocket expenditure in Australia. Data also suggest CAM use is highest amongst rural Australians. Unfortunately little is known about the grass-roots reality of naturopathy or other CAM use in rural regions. Methods. Semi-structured interviews were conducted with 20 naturopaths practising in the Darling Downs region of South-East Queensland to assess their perceptions and experiences of rural patients and demand for their services. Results. Naturopaths described strong demand in rural areas for their services and perceived much of this demand as attributable to cultural traits in rural communities that served as pull factors for their naturopathic services. Such perceived traits included a cultural affinity for holistic approaches to health and disease and the preventive philosophy of naturopathy and an appreciation of the core tenet of naturopathic practice to develop closer therapeutic relationships. However, cost and a rural culture of self-reliance were seen as major barriers to naturopathic practice in rural areas. Conclusions. Demand for naturopathic services in rural areas may have strong underlying cultural and social drivers. Given the apparent affinity for and increasingly large role played by CAM services, including naturopathic medicine, in rural areas it is imperative that naturopathic medicine and the CAM sector more broadly become a core focus of rural health research

Evolving the theory and praxis of knowledge translation through social interaction: a social phenomenological study

Background: As an inherently human process fraught with subjectivity, dynamic interaction, and change, social interaction knowledge translation (KT) invites implementation scientists to explore what might be learned from adopting the academic tradition of social constructivism and an interpretive research approach. This paper presents phenomenological investigation of the second cycle of a participatory action KT intervention in the home care sector to answer the question: What is the nature of the process of implementing KT through social interaction? Methods: Social phenomenology was selected to capture how the social processes of the KT intervention were experienced, with the aim of representing these as typical socially-constituted patterns. Participants (n = 203), including service providers, case managers, administrators, and researchers organized into nine geographically-determined multi-disciplinary action groups, purposefully selected and audiotaped three meetings per group to capture their enactment of the KT process at early, middle, and end-of-cycle timeframes. Data, comprised of 36 hours of transcribed audiotapes augmented by researchers\u27 field notes, were analyzed using social phenomenology strategies and authenticated through member checking and peer review. Results: Four patterns of social interaction representing organization, team, and individual interests were identified: overcoming barriers and optimizing facilitators; integrating \u27science push\u27 and \u27demand pull\u27 approaches within the social interaction process; synthesizing the research evidence with tacit professional craft and experiential knowledge; and integrating knowledge creation, transfer, and uptake throughout everyday work. Achieved through relational transformative leadership constituted simultaneously by both structure and agency, in keeping with social phenomenology analysis approaches, these four patterns are represented holistically in a typical construction, specifically, a participatory action KT (PAKT) model. Conclusion: Study findings suggest the relevance of principles and foci from the field of process evaluation related to intervention implementation, further illuminating KT as a structuration process facilitated by evolving transformative leadership in an active and integrated context. The model provides guidance for proactively constructing a \u27fit\u27 between content, context, and facilitation in the translation of evidence informing professional craft knowledge

Aboriginal Women Caregivers of the Elderly

Introduction: The purpose of this qualitative study was to develop a comprehensive understanding of Aboriginal women\u27s experiences and perceptions of providing care to the elderly in geographically isolated communities (GIC). Research with Aboriginal women caregivers is essential as the population of Aboriginal elders is increasing, and Aboriginal women represent the majority of caregivers in their communities. Methods: This study was guided by focused ethnography, which seeks an understanding of a sub-group within a cultural group by uncovering the less obvious expressions and behaviours of the sub-group members. Using one-on-one open-ended interviews and participant observation, 13 women from a number of Aboriginal communities in northern and southern Ontario participated in this study. Data analysis was conducted by reviewing transcripts of interviews to identify codes and themes. Results: Study findings revealed that four concentric circles represent the caring experiences of the Aboriginal women participants: the healers, the family, the Aboriginal community, and the non-Aboriginal community. Cultural values greatly informed participants\u27 perceptions about caring for elderly persons in GIC. These values are represented in five themes: passing on traditions, being chosen to care, supporting the circle of healers, (re)establishing the circles of care, and accepting/refusing external resources. Conclusion: The findings from this study have significant implications for healthcare practice and future research