39 research outputs found
Early-Onset Progressive Degeneration of the Area Centralis in RPE65-Deficient Dogs.
PURPOSE:
Retinal epithelium-specific protein 65 kDa (RPE65)-deficient dogs are a valuable large animal model species that have been used to refine gene augmentation therapy for Leber congenital amaurosis type-2 (LCA2). Previous studies have suggested that retinal degeneration in the dog model is slower than that observed in humans. However, the area centralis of the dog retina is a cone and rod photoreceptor rich region comparable to the human macula, and the effect of RPE65 deficiency specifically on this retinal region, important for high acuity vision, has not previously been reported.
METHODS:
Spectral-domain optical coherence tomography, fundus photography, and immunohistochemistry of retinal wholemounts and sagittal frozen sections were used to define the time-course and cell-types affected in degeneration of the area centralis in affected dogs.
RESULTS:
Area centralis photoreceptor degeneration was evident from 6 weeks of age, and progressed to involve the inner retina. Immunohistochemistry showed that RPE65-deficient dogs developed early loss of S-cone outer segments, with slower loss of L/M-cone outer segments and rods.
CONCLUSIONS:
Early-onset severe photoreceptor degeneration in the area centralis of dogs with RPE65-deficiency offers a model of the early foveal/perifoveal degeneration in some patients with LCA2. This model could be used to refine interventions aiming to improve function and halt the progression of foveal/perifoveal photoreceptor degeneration
The association between green space and cause-specific mortality in urban New Zealand: an ecological analysis of green space utility
<b>Background:</b>
There is mounting international evidence that exposure to green environments is associated with health benefits, including lower mortality rates. Consequently, it has been suggested that the uneven distribution of such environments may contribute to health inequalities. Possible causative mechanisms behind the green space and health relationship include the provision of physical activity opportunities, facilitation of social contact and the restorative effects of nature. In the New Zealand context we investigated whether there was a socioeconomic gradient in green space exposure and whether green space exposure was associated with cause-specific mortality (cardiovascular disease and lung cancer). We subsequently asked what is the mechanism(s) by which green space availability may influence mortality outcomes, by contrasting health associations for different types of green space.
<b>Methods:</b>
This was an observational study on a population of 1,546,405 living in 1009 small urban areas in New Zealand. A neighbourhood-level classification was developed to distinguish between usable (i.e., visitable) and non-usable green space (i.e., visible but not visitable) in the urban areas. Negative binomial regression models were fitted to examine the association between quartiles of area-level green space availability and risk of mortality from cardiovascular disease (n = 9,484; 1996 - 2005) and from lung cancer (n = 2,603; 1996 - 2005), after control for age, sex, socio-economic deprivation, smoking, air pollution and population density.
<b>Results:</b>
Deprived neighbourhoods were relatively disadvantaged in total green space availability (11% less total green space for a one standard deviation increase in NZDep2001 deprivation score, p < 0.001), but had marginally more usable green space (2% more for a one standard deviation increase in deprivation score, p = 0.002). No significant associations between usable or total green space and mortality were observed after adjustment for confounders.
<b>Conclusion</b>
Contrary to expectations we found no evidence that green space influenced cardiovascular disease mortality in New Zealand, suggesting that green space and health relationships may vary according to national, societal or environmental context. Hence we were unable to infer the mechanism in the relationship. Our inability to adjust for individual-level factors with a significant influence on cardiovascular disease and lung cancer mortality risk (e.g., diet and alcohol consumption) will have limited the ability of the analyses to detect green space effects, if present. Additionally, green space variation may have lesser relevance for health in New Zealand because green space is generally more abundant and there is less social and spatial variation in its availability than found in other contexts
AAV2-Mediated Subretinal Gene Transfer of hIFN-α Attenuates Experimental Autoimmune Uveoretinitis in Mice
BACKGROUND: Recent reports show that gene therapy may provide a long-term, safe and effective intervention for human diseases. In this study, we investigated the effectiveness of adeno-associated virus 2 (AAV2) based human interferon-alpha (hIFN-α) gene therapy in experimental autoimmune uveoretinitis (EAU), a classic model for human uveitis. METHODOLOGY/PRINCIPAL FINDINGS: An AAV2 vector harboring the hIFN-α gene (AAV2.hIFN-α) was subretinally injected into B10RIII mice at two doses (1.5×10(6) vg, 1.5×10(8) vg). AAV2 vector encoding green fluorescent protein (AAV2.GFP) was used as a control (5×10(8) vg). The expression of hIFN-α in homogenized eyes and serum was detected by ELISA three weeks after injection. The biodistribution of vector DNA in the injected eyes, contralateral eyes and distant organs was determined by PCR. EAU was induced by immunization with IRBP(161-180) three weeks following vector injections, and evaluated clinically and pathologically. IRBP-specific proliferation and IL-17 expression of lymphocytes from the spleen and lymph nodes were assayed to test the influence of the subretinal delivery of AAV2.hIFN-α on the systemic immune response. hIFN-α was effectively expressed in the eyes from three weeks to three months following subretinal injection of AAV2.hIFN-α vector. DNA of AAV2.GFP was observed only in the injected eyes, but not in the distant organs or contralateral eyes. Subretinal injection of both doses significantly attenuated EAU activity clinically and histologically. For the lower dose, there was no difference concerning lymphocyte proliferation and IL-17 production among the AAV2.hIFN-α, AAV2.GFP and PBS injected mice. However, the higher dose of AAV2.hIFN-α significantly suppressed lymphocyte proliferation and IL-17 production. CONCLUSIONS/SIGNIFICANCE: Subretinal delivery of AAV2.hIFN-α lead to an effective expression within the eye for at least three months and significantly attenuated EAU activity. AAV2.hIFN-α was shown to inhibit the systemic IRBP-specific immune response
Inequitable walking conditions among older people: examining the interrelationship of neighbourhood socio-economic status and urban form using a comparative case study
<p>Abstract</p> <p>Background</p> <p>Supportive neighbourhood walking conditions are particularly important for older people as they age and who, as a group, prefer walking as a form of physical activity. Urban form and socio-economic status (SES) can influence neighbourhood walking behaviour. The objectives of this study were: a) to examine how urban form and neighbourhood SES inter-relate to affect the experiences of older people who walk in their neighbourhoods; b) to examine differences among neighbourhood stakeholder key informant perspectives on socio-political processes that shape the walkability of neighbourhood environments.</p> <p>Methods</p> <p>An embedded comparative case study examined differences among four Ottawa neighbourhoods that were purposefully selected to provide contrasts on urban form (inner-urban versus suburban) and SES (higher versus lower). Qualitative data collected from 75 older walkers and 19 neighbourhood key informants, as well as quantitative indicators were compared on the two axes of urban form and SES among the four neighbourhoods.</p> <p>Results and discussion</p> <p>Examining the inter-relationship of neighbourhood SES and urban form characteristics on older people's walking experiences indicated that urban form differences were accentuated positively in higher SES neighbourhoods and negatively in lower SES neighbourhoods. Older people in lower SES neighbourhoods were more affected by traffic hazards and more reliant on public transit compared to their higher SES counterparts. In higher SES neighbourhoods the disadvantages of traffic in the inner-urban neighbourhood and lack of commercial destinations in the suburban neighbourhood were partially offset by other factors including neighbourhood aesthetics. Key informant descriptions of the socio-political process highlighted how lower SES neighbourhoods may face greater challenges in creating walkable places. These differences pertained to the size of neighbourhood associations, relationships with political representatives, accessing information and salient neighbourhood association issues. Findings provide evidence of inequitable walking environments.</p> <p>Conclusion</p> <p>Future research on walking must consider urban form-SES inter-relationships and further examine the equitable distribution of walking conditions as well as the socio-political processes driving these conditions. There is a need for municipal governments to monitor differences in walking conditions among higher and lower SES neighbourhoods, to be receptive to the needs of lower SES neighbourhood and to ensure that policy decisions are taken to address inequitable walking conditions.</p
A mobile hospice nurse teaching team’s experience: training care workers in spiritual and existential care for the dying - a qualitative study
Understanding the relationships between the physical environment and physical activity in older adults: a systematic review of qualitative studies
Association between social and built environments and leisure-time physical activity among Chinese older adults - a multilevel analysis
Residents with mild cognitive decline and family members report health students 'enhance capacity of care' and bring 'a new breath of life' in two aged care facilities in Tasmania.
BACKGROUND: Care provided by student doctors and nurses is well received by patients in hospital and primary care settings. Whether the same is true for aged care residents of nursing homes with mild cognitive decline and their family members is unknown. OBJECTIVE: To investigate the perspectives of aged care residents with mild cognitive decline and their family members on interdisciplinary student placements in two residential aged care facilities (RACF) in Tasmania. DESIGN, SETTING AND PARTICIPANTS: A mixed methods design was employed with both qualitative and quantitative data collected. All participants were interviewed and completed a questionnaire on residents' quality of life, during or after a period of student placements in each facility (October-November, 2012). Qualitative data were coded for themes following a grounded theory approach, and quantitative data were analysed using SPSS. RESULTS: Twenty-one participants (13 residents and 8 family members) were recruited. Four themes were identified from the qualitative data and included (i) increased social interaction and facility vibrancy; (ii) community service and personal development, (iii) vulnerability and sensitivity (learning to care) and (iv) increased capacity and the confidence of enhanced care. Residents' quality of life was reported to be mostly good in the presence of the students, despite their high care needs. CONCLUSION: Residents with mild cognitive decline and their family members perceive a wide array of benefits of student provided care in RACFs including increased social interaction. Future quantitative research should focus on whether changes in care occur for residents as a result of student involvement