3,759 research outputs found
Pharmacological profiling of the hemodynamic effects of cannabinoid ligands: a combined in vitro and in vivo approach
The receptors mediating the hemodynamic responses to cannabinoids are not clearly defined due to the multifarious pharmacology of many commonly used cannabinoid ligands. While both CB1 and TRPV1 receptors are implicated, G protein-coupled receptor 55 (GPR55) may also mediate some of the hemodynamic effects of several atypical cannabinoid ligands. The present studies attempted to unravel the pharmacology underlying the in vivo hemodynamic responses to ACEA (CB1 agonist), O-1602 (GPR55 agonist), AM251 (CB1 antagonist), and cannabidiol (CBD; GPR55 antagonist). Agonist and antagonist profiles of each ligand were determined by ligand-induced GTPγS binding in membrane preparations expressing rat and mouse CB1 and GPR55 receptors. Blood pressure responses to ACEA and O-1602 were recorded in anesthetized and conscious mice (wild type, CB1−/− and GPR55−/−) and rats in the absence and presence of AM251 and CBD. ACEA demonstrated GTPγS activation at both receptors, while O-1602 only activated GPR55. AM251 exhibited antagonist activity at CB1 and agonist activity at GPR55, while CBD demonstrated selective antagonist activity at GPR55. The depressor response to ACEA was blocked by AM251 and attenuated by CBD, while O-1602 did not induce a depressor response. AM251 caused a depressor response that was absent in GPR55−/− mice but enhanced by CBD, while CBD caused a small vasodepressor response that persisted in GPR55−/− mice. Our findings show that assessment of the pharmacological profile of receptor activation by cannabinoid ligands in in vitro studies alongside in vivo functional studies is essential to understand the role of cannabinoids in hemodynamic control
Foot pain and foot health in an educated population of adults: results from the Glasgow Caledonian University Alumni Foot Health Survey
Abstract Background Foot pain is common amongst the general population and impacts negatively on physical function and quality of life. Associations between personal health characteristics, lifestyle/behaviour factors and foot pain have been studied; however, the role of wider determinants of health on foot pain have received relatively little attention. Objectives of this study are i) to describe foot pain and foot health characteristics in an educated population of adults; ii) to explore associations between moderate-to-severe foot pain and a variety of factors including gender, age, medical conditions/co-morbidity/multi-morbidity, key indicators of general health, foot pathologies, and social determinants of health; and iii) to evaluate associations between moderate-to-severe foot pain and foot function, foot health and health-related quality-of-life. Methods Between February and March 2018, Glasgow Caledonian University Alumni with a working email address were invited to participate in the cross-sectional electronic survey (anonymously) by email via the Glasgow Caledonian University Alumni Office. The survey was constructed using the REDCap secure web online survey application and sought information on presence/absence of moderate-to-severe foot pain, patient characteristics (age, body mass index, socioeconomic status, occupation class, comorbidities, and foot pathologies). Prevalence data were expressed as absolute frequencies and percentages. Multivariate logistic and linear regressions were undertaken to identify associations 1) between independent variables and moderate-to-severe foot pain, and 2) between moderate-to-severe foot pain and foot function, foot health and health-related quality of life. Results Of 50,228 invitations distributed, there were 7707 unique views and 593 valid completions (median age [inter-quartile range] 42 [31–52], 67.3% female) of the survey (7.7% response rate). The sample was comprised predominantly of white Scottish/British (89.4%) working age adults (95%), the majority of whom were overweight or obese (57.9%), and in either full-time or part-time employment (82.5%) as professionals (72.5%). Over two-thirds (68.5%) of the sample were classified in the highest 6 deciles (most affluent) of social deprivation. Moderate-to-severe foot pain affected 236/593 respondents (39.8%). High body mass index, presence of bunions, back pain, rheumatoid arthritis, hip pain and lower occupation class were included in the final multivariate model and all were significantly and independently associated with moderate-to-severe foot pain (p < 0.05), except for rheumatoid arthritis (p = 0.057). Moderate-to-severe foot pain was significantly and independently associated lower foot function, foot health and health-related quality of life scores following adjustment for age, gender and body mass index (p < 0.05). Conclusions Moderate-to-severe foot pain was highly prevalent in a university-educated population and was independently associated with female gender, high body mass index, bunions, back pain, hip pain and lower occupational class. Presence of moderate-to-severe foot pain was associated with worse scores for foot function, foot health and health-related quality-of-life. Education attainment does not appear to be protective against moderate-to-severe foot pain
A qualitative exploration of the effect of visual field loss on daily life in home-dwelling stroke survivors
Objective: To explore the effect of visual field loss on the daily life of community-dwelling stroke survivors. Design: A qualitative interview study. Participants: Adult stroke survivors with visual field loss of at least six months’ duration. Methods: Semi-structured interviews were conducted with a non-purposive sample of 12 stroke survivors in their own homes. These were recorded, transcribed verbatim and analyzed with the framework method, using an inductive approach. Results: Two key analytical themes emerged. ‘Perception, experience and knowledge’ describes participant’s conflicted experience of having knowledge of their impaired vision but lacking perception of that visual field loss and operating under the assumption that they were viewing an intact visual scene when engaged in activities. Inability to recognize and deal with visual difficulties, and experiencing the consequences, contributed to their fear and loss of self-confidence. ‘Avoidance and adaptation’ were two typologies of participant response to visual field loss. Initially, all participants consciously avoided activities. Some later adapted to vision loss using self-directed head and eye scanning techniques. Conclusions: Visual field loss has a marked impact on stroke survivors. Stroke survivors lack perception of their visual loss in everyday life, resulting in fear and loss of confidence. Activity avoidance is a common response, but in some, it is replaced by self-initiated adaptive techniques
Which circulating antioxidant vitamins are confounded by socioeconomic deprivation? The MIDSPAN family study
<p><b>Background:</b> Antioxidant vitamins are often described as having “independent” associations with risk of cancer, cardiovascular disease (CVD) and mortality. We aimed to compare to what extent a range of antioxidant vitamins and carotenoids are associated with adulthood and childhood markers of socioeconomic deprivation and to adverse lifestyle factors.</p>
<p><b>Methods and Findings:</b> Socioeconomic and lifestyle measures were available in 1040 men and 1298 women from the MIDSPAN Family Study (30–59 years at baseline) together with circulating levels of vitamins A, C, E, and carotenoids (α-carotene, β-carotene, lutein and lycopene). Markers of socioeconomic deprivation in adulthood were consistently as strongly associated with lower vitamin C and carotenoid levels as markers of adverse lifestyle; the inverse association with overcrowding was particularly consistent (vitamin C and carotenoids range from 19.1% [95% CI 30.3–6.0] to 38.8% [49.9–25.3] lower among those in overcrowded residencies). These associations were consistent after adjusting for month, classical CVD risk factors, body mass index, physical activity, vitamin supplements, dietary fat and fibre intake. Similar, but weaker, associations were seen for childhood markers of deprivation. The association of vitamin A or E were strikingly different; several adult adverse lifestyle factors associated with higher levels of vitamin A and E, including high alcohol intake for vitamin A (9.5% [5.7–13.5]) and waist hip ratio for vitamin E (9.5% [4.8–14.4]), with the latter associations partially explained by classical risk factors, particularly cholesterol levels.</p>
<p><b>Conclusions:</b> Plasma vitamin C and carotenoids have strong inverse associations with adulthood markers of social deprivation, whereas vitamin A and E appear positively related to specific adverse lifestyle factors. These findings should help researchers better contextualize blood antioxidant vitamin levels by illustrating the potential limitations associated with making causal inferences without consideration of social deprivation.</p>
Translating policy to place: exploring cultural ecosystem services in areas of Green Belt through participatory mapping
\ua9 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.Green Belts are longstanding planning designations, which primarily seek to prevent urban sprawl. Importantly, they form the open spaces close to where most people live, but we lack clarity over how Green Belts are used and valued by publics, and the cultural ecosystem services they provide. To address this policy and research gap, a public participatory mapping survey was conducted on the North-East England Green Belt, with 779 respondents plotting 2388 points. The results show for the first time that in addition to being a planning policy zone, Green Belts are important, and widely used open spaces for ‘everyday nature’, providing several cultural ecosystem services including recreation, connection with nature, sense of place and aesthetic value. Several factors were found to influence the supply of cultural ecosystem services in Green Belts, including proximity to urban areas, woodland land cover and access designations. Whereas most demand pressures on Green Belts were on public rights-of-way, nature designations and deciduous woodlands. Pervasive barriers inhibiting Green Belt’s full potential were identified including management issues, concerns over personal safety and lack of access. We argue that opportunities to further enhance the cultural ecosystem services provided Green Belts and peri-urban landscapes more broadly, not only come from planning policies themselves, but from the design and delivery of approaches integrating urban, rural and land-use policy silos. The findings have wider implications for policy including potential conflict with future development, and opportunities for greater access to greenspace
Urban flood risk management through the lens of citizen science: A case study on the two city corporations’ area of Dhaka
\ua9 2025 The AuthorsDhaka is one of the most densely populated cities in South Asia. In recent times, prolonged urban flooding/water logging is a recurring phenomenon and major concern in the two city corporations\u27 areas. This study investigates how “citizen science” could help individuals, communities, and stakeholders to understand and manage the risk of current and future urban flooding, by integrating people\u27s experience, concerns, and opinions on flood risk management into the formal framework. A questionnaire survey was conducted among 500 respondents in water logging affected wards of Dhaka. We identified that every year respondents in two city corporations experience 1–3 days of water logging, mostly during the monsoon season. Respondents were found to be aware about flooding and its associated risks and emphasised a concern about the increasing frequency of urban flooding in Dhaka over the next 10 years. Although 61.2% of the respondents were not familiar with the concept of citizen science, 42.8% of respondents expressed eagerness to become involved in any related project to promote awareness and mitigation of urban flooding issues in their communities. Key stakeholder and focus group discussions exposed that unplanned urbanisation, poor drainage system management, inappropriate waste management systems, and recent extreme rainfall events are the major perceived drivers behind urban flooding in Dhaka. Our discussions emphasised the need for integration of both modelling and geospatial techniques to build a Volunteer Geographic Information (VGI) system for the mitigation. We conclude that citizen science approach could play a significant role in tackling urban flooding risks in Dhaka
An extragalactic supernebula confined by gravity
Little is known about the origins of the giant star clusters known as
globular clusters. How can hundreds of thousands of stars form simultaneously
in a volume only a few light years across the distance of the sun to its
nearest neighbor? Radiation pressure and winds from luminous young stars should
disperse the star-forming gas and disrupt the formation of the cluster.
Globular clusters in our Galaxy cannot provide answers; they are billions of
years old. Here we report the measurement of infrared hydrogen recombination
lines from a young, forming super star cluster in the dwarf galaxy, NGC 5253.
The lines arise in gas heated by a cluster of an estimated million stars, so
young that it is still enshrouded in gas and dust, hidden from optical view. We
verify that the cluster contains 4000-6000 massive, hot "O" stars. Our
discovery that the gases within the cluster are bound by gravity may explain
why these windy and luminous O stars have not yet blown away the gases to allow
the cluster to emerge from its birth cocoon. Young clusters in "starbursting"
galaxies in the local and distant universe may be similarly gravitationally
confined and cloaked from view.Comment: Letter to Natur
Validation and development of extravascular bubble models for decompression sickness using collagen hydrogel
For over 200 years, the formation of bubbles in the body as a result of ambient pres- sure changes has been linked to decompression sickness (DCS). The mechanisms by which bubbles may lead to DCS are poorly understood, despite this long history of re- search. Mathematical modelling has played a key role in DCS prevention through the development of dive computer algorithms. Algorithms which incorporate mechanistic bubble models must make assumptions about a selected bubble property being statisti- cally related to the incidence of DCS. This poses a problem for the validation of such algorithms. Given the uncertain relationship between the mechanistic model output and the symptoms of DCS, direct bubble observation is required to validate the mechanistic portion of the model; such measurements, however, are not currently possible in vivo. The use of biomimetic in vitro models provides a new research avenue to investigate the causal mechanism as well address the validation problem currently faced. In the work described in this thesis an in vitro matrix model (collagen type I gel) was used to validate and further develop a 3D computational model of extravascular bubble dynamics. The collagen gels together with a microscope compatible pressure chamber provided the means to directly measure bubble formation and dynamics within the gels during decompression profiles. The effect of material and dive parameter vari- ations on bubble growth was first investigated and validated. Bubble-bubble interaction and coalescence were then analysed. Both the computational and experimental results of these analyses indicated that a model of bubble nucleation would be essential to model bubble dynamics accurately. The possible nature and distribution of nucleation sites was investigated. Options for incorporation of the nucleation findings are anal- ysed. Finally the influence of live cells bubble dynamics through oxygen consumption and the effect bubble proximity has on cell viability were investigated
Prevalence of Disorders Recorded in Dogs Attending Primary-Care Veterinary Practices in England
Purebred dog health is thought to be compromised by an increasing occurence of inherited diseases but inadequate prevalence data on common disorders have hampered efforts to prioritise health reforms. Analysis of primary veterinary practice clinical data has been proposed for reliable estimation of disorder prevalence in dogs. Electronic patient record (EPR) data were collected on 148,741 dogs attending 93 clinics across central and south-eastern England. Analysis in detail of a random sample of EPRs relating to 3,884 dogs from 89 clinics identified the most frequently recorded disorders as otitis externa (prevalence 10.2%, 95% CI: 9.1-11.3), periodontal disease (9.3%, 95% CI: 8.3-10.3) and anal sac impaction (7.1%, 95% CI: 6.1-8.1). Using syndromic classification, the most prevalent body location affected was the head-and-neck (32.8%, 95% CI: 30.7-34.9), the most prevalent organ system affected was the integument (36.3%, 95% CI: 33.9-38.6) and the most prevalent pathophysiologic process diagnosed was inflammation (32.1%, 95% CI: 29.8-34.3). Among the twenty most-frequently recorded disorders, purebred dogs had a significantly higher prevalence compared with crossbreds for three: otitis externa (P = 0.001), obesity (P = 0.006) and skin mass lesion (P = 0.033), and popular breeds differed significantly from each other in their prevalence for five: periodontal disease (P = 0.002), overgrown nails (P = 0.004), degenerative joint disease (P = 0.005), obesity (P = 0.001) and lipoma (P = 0.003). These results fill a crucial data gap in disorder prevalence information and assist with disorder prioritisation. The results suggest that, for maximal impact, breeding reforms should target commonly-diagnosed complex disorders that are amenable to genetic improvement and should place special focus on at-risk breeds. Future studies evaluating disorder severity and duration will augment the usefulness of the disorder prevalence information reported herein
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