Studies on the role of GPR55 in cardiovascular physiology and pathophysiology.

Atherosclerosis is a multifactorial, chronic inflammatory condition characterised by endothelial dysfunction, hyperlipidaemia and the accumulation of fatty deposits within the tunica intima of medium-to-large sized muscular arteries. This disease can prove fatal with patients suffering lethal myocardial infarction or stroke. Recently, two studies investigating the role of G-protein-coupled receptor 55 (GPR55) in atherosclerosis reported conflicting results; one reported a pro-atherogenic role for GPR55 and the other, an anti-atherogenic role for this receptor. Interestingly, another study demonstrated that the activation of GPR55 by lysophosphatidylinositol (LPI) in cultured rat neonatal ventricular cardiomyocytes provokes distinct cellular functions that are dependent on the location of GPR55, leading to suggestions that GPR55 may regulate cardiomyocyte function at two cellular sites and be a potential therapeutic target for cardiac disorders. While it has been demonstrated that GPR55 is important in the maintenance of cardiac function of healthy mice, what is currently unknown is if GPR55 has a role in the cardiovascular remodelling and cardiac function of atherosclerosis prone mice. To address this, the present studies were conducted to investigate 1) the role of GPR55 in atherogenesis, 2) if GPR55 has a role in the cardiac function of mice suffering from atherosclerosis, 3) the signalling pathway by which LPI activates cardiomyocytes, 4) the impact of GPR55 activation on the outcome of myocardial ischaemia/reperfusion (I/R) injury and, 5) the signalling mechanisms by which GPR55 elicits any observed effects on the myocardium in response to such injury. Using C57BL/6 (wildtype; WT), apolipoprotein E knockout (ApoE-/-; mouse model of atherosclerosis), GPR55 knockout (GPR55-/-) and novel ApoE-/-/GPR55-/- mice, this study has established that in the presence of high fat feeding (to accelerate atherosclerosis), GPR55 has a complex role whereby it both regulates risk factors associated with atherosclerosis (i.e. body weight and fat mass) yet promotes the development of fatty streaks within the vasculature, via a lipid independent mechanism. In terms of cardiac function, GPR55 exerted a protective role by maintaining the systolic function of high fat fed ApoE-/- mice, yet negatively affected the contractile reserve of these mice. With regard to infarct size, the present study established that LPI-induced activation of GPR55 (pre-global ischaemia) exacerbates myocardial tissue injury via a Rho-associated protein kinase (ROCK) dependent mechanism. Finally, this study established that LPI signals through the same signalling pathway as it did in the isolated heart, in both mouse and human-induced pluripotent stem cell-derived cardiomyocytes thus suggesting a translational role for GPR55 in the human heart. In conclusion, despite further research being required, the data presented within this thesis provides evidence that GPR55 may have the potential to be targeted for therapeutic gains in atherosclerosis and myocardial I/R injury

Effect of Microwaved Water on the Growth of Tomato (Lycopersicon esculentum) Seedlings

The purpose of this project was to investigate the effects of microwave-heated water on the growth of tomato (Lycopersicon esculentum) seedlings, in order to observe the effects of microwave radiation. Three groups of seedlings were used, one treated with tap water, one with microwaved water and one with boiled water and these were studied for 5 weeks. Analysis of the results showed that both microwaved and boiled water increased the overall growth rate of the length of the stem of the seedlings compared to tap water, with boiled water having the most positive effect. This suggests that the effects of microwave radiation were not harmful to the treated plants and therefore the use of microwave appliances in households to heat substances for human consumption may not alter these substances negatively or affect human health

Identifying meaningful facial configurations during iterative prisoner’s dilemma games

The contraction and relaxation of facial muscles in humans is widely assumed to fulfil communicative and adaptive functions. However, to date most work has focussed either on individual muscle movements (action units) in isolation or on a small set of configurations commonly assumed to express “basic emotions”. As such, it is as yet unclear what information is communicated between individuals during naturalistic social interactions and how contextual cues influence facial activity occurring in these exchanges. The present study investigated whether consistent patterns of facial action units occur during dyadic iterative prisoners’ dilemma games, and what these patterns of facial activity might mean. Using exploratory and confirmatory factor analyses, we identified three distinct and consistent configurations of facial musculature change across three different datasets. These configurations were associated with specific gameplay outcomes, suggesting that they perform psychologically meaningful context-related functions. The first configuration communicated enjoyment and the second communicated affiliation and appeasement, both indicating cooperative intentions after cooperation or defection respectively. The third configuration communicated disapproval and encouraged social partners not to defect again. Future work should validate the occurrence and functionality of these facial configurations across other kinds of social interaction

Comparative safety and effectiveness of direct oral anticoagulants in patients with atrial fibrillation in clinical practice in Scotland

To compare the clinical effectiveness and safety of direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF) in routine clinical practice. Retrospective cohort study using linked administrative data. The study population (n=14,577) included patients with a diagnosis of AF (confirmed in hospital) who initiated DOAC treatment in Scotland between August 2011 and December 2015. Multivariate Cox proportional hazard models were used to estimate hazard ratios of thromboembolic events, mortality, and bleeding events. No differences between the DOACs were observed in the risks of stroke, systemic embolism, or cardiovascular death. In contrast, the risk of myocardial infarction was higher among apixaban patients in comparison to rivaroxaban (1.67 [1.02 - 2.71]), and all-cause mortality was higher among rivaroxaban patients in contrast to both apixaban (1.22 [1.01 - 1.47]) and dabigatran (1.55 [1.16 - 2.05]); rivaroxaban patients also had a higher risk of pulmonary embolism than apixaban patients (5.27 [1.79 - 15.53]). The risk of other major bleeds was higher among rivaroxaban patients compared to apixaban (1.50 [1.10 - 2.03]) and dabigatran (1.58 [1.01 - 2.48]); the risks of gastro-intestinal bleeds and overall bleeding were higher among rivaroxaban patients than among apixaban patients (1.48 [1.01 - 2.16] and 1.52[1.21 - 1.92], respectively). All DOACs were similarly effective in preventing strokes and systemic embolisms, while patients being treated with rivaroxaban exhibited the highest bleeding risks. Observed differences in the risks of all-cause mortality, myocardial infarction, and pulmonary embolism warrant further research. [Abstract copyright: This article is protected by copyright. All rights reserved.

Proxy rated quality of life of care home residents with dementia: a systematic review

Quality of life (QoL) is an important outcome for people with dementia living in care homes but usually needs to be rated by a proxy. We do not know if relative or paid carer proxy reports differ. We conducted the first systematic review and meta-analysis of data investigating whether and how these proxy reports of QoL differ. We searched four databases: Medline, Embase, PsychInfo, and CINAHL in October 2015 with the terms: dementia, QoL, proxy, and care home. Included studies either compared proxy QoL ratings or investigated the factors associated with them. We meta-analyzed data comparing staff and family proxy rated QoL. We included 17/105 papers identified. We found no difference between global proxy ratings of QoL (n = 1,290; pooled effect size 0.06 (95% CI = −0.08 to 0.19)). Studies investigating factors associated with ratings (n = 3,537) found family and staff ratings correlated with the resident's physical and mental health. Staff who were more distressed rated resident QoL lower. Relatives rated it lower when the resident had lived in the care home for longer, when they observed more restraint, or contributed more to fees. Relatives and staff proxy QoL ratings share a clear relationship to resident health and overall ratings were similar. Rater-specific factors were, however, also associated with scores. Understanding why different raters consider the QoL of the same person differently is an important consideration when evaluating the meaning of proxy rated QoL. Proxy raters’ backgrounds may affect their rating of QoL

Leaving or Staying “Home” in a Time of Rupture: International Students’ Experiences of Loneliness and Social Isolation during COVID-19

Olivia Sagan - ORCID: 0000-0001-6128-8499 https://orcid.org/0000-0001-6128-8499Mhairi Scally-Robertson - ORCID: https://orcid.org/0000-0002-3740-5285AM replaced with VoR 2024-01-15.During COVID-19, international students were faced with the decision of remaining in their country of study or returning to their home countries, with little knowledge of when they would next be able to return or leave. Both choices left the students vulnerable to feelings of loneliness and social isolation. This paper examines how international students at a Scottish university experienced and navigated leaving or staying “home” and how loneliness and social isolation characterised these experiences. We further contextualise these experiences through Holbraad et al.’s (2019) prism of “rupture”. The data were generated between February-July 2021 through semi-structured focus groups and qualitative questionnaire comments and were analysed through Thematic Analysis. We discuss three themes: 1) Liminal Friends and Strangers, 2) Sense of Home and Family, and 3) Staying or Leaving the Country. The study contributes to the expanding body of research on experiences of loneliness and social isolation amongst international students.pubpu

Cyclophilin D palmitoylation and permeability transition: a new twist in the tale of myocardial ischaemia-reperfusion injury

No abstract available

l-α-Lysophosphatidylinositol (LPI) aggravates myocardial ischemia/reperfusion injury via a GPR55/ROCK-dependent pathway

The phospholipid l-α-lysophosphatidylinositol (LPI), an endogenous ligand for GPR55, is elevated in patients with acute coronary syndrome, and a GPR55 antagonist cannabidiol (CBD) reduces experimental ischemia/reperfusion (I/R) injury. While LPI activates multiple signaling pathways, little is known about which ones are important in cardiomyocytes. In this study we explored whether activation of the Rho kinase/ROCK/p38 MAPK pathway is responsible for LPI-induced extension of I/R injury. Using a high-throughput screening method (dynamic mass redistribution; DMR), mouse- and human-induced pluripotent stem cell (iPSC) cardiomyocytes exposed to LPI were shown to exhibit a rapid, sustained, and concentration‐dependent (1 nmol L−1‐30 μmol L−1) cellular response. Y‐27632 (ROCK inhibitor; 10 & 50 μmol L−1) and CBD (1 μmol L−1) both abolished the DMR response to LPI (10 μmol L−1). In murine iPSC cardiomyocytes, LPI-induced ROCK and p38 MAPK phosphorylation, both of which were prevented by Y-27632 and CBD, but did not induce JNK activation or cleavage of caspase-3. In hearts isolated from wild type (WT) mice subjected to 30 minutes global I/R, LPI (10 μmol L−1) administered via the coronary circulation increased infarct size when applied prior to ischemia onset, but not when given at the time of reperfusion. The exacerbation of tissue injury by LPI was not seen in hearts from GPR55−/− mice or in the presence of Y-27632, confirming that injury is mediated via the GPR55/ROCK/p38 MAPK pathway. These findings suggest that raised levels of LPI in the vicinity of a developing infarct may worsen the outcome of AMI

How do care home staff understand, manage and respond to agitation in people with dementia? A qualitative study

Objectives: Little is known about how care home staff understand and respond to distress in residents living with dementia labelled as agitation. The aim of this study was to describe how care home staff understand and respond to agitation and the factors that determine how it is managed. Design: We conducted a qualitative thematic analysis. Setting: We recruited staff from six care homes in South East England including residential and nursing homes of differing sizes run by both the private and charity sector and located in urban and rural areas. Participants: We interviewed 25 care home staff using purposive sampling to include staff of either sex, differing age, ethnicity, nationality and with different roles and experience. Results: We identified four overarching themes: (1) behaviours expressing unmet need; (2) staff emotional responses to agitation; (3) understanding the individual helps and (4) constraints on staff responses. Staff struggled with the paradox of trying to connect with the personhood of residents while seeing the person as separate to and, therefore, not responsible for their behaviours. Staff often felt powerless, frightened and overwhelmed, and their responses were constrained by care home structures, processes and a culture of fear and scrutiny. Conclusions: Responding to agitation expressed by residents was not a linear process and staff faced tensions and dilemmas in deciding how to respond, especially when initial strategies were unsuccessful or when attempts to respond to residents’ needs were inhibited by structural and procedural constraints in the care home. Future trials of psychosocial interventions should support staff to identify and respond to residents’ unmet needs and include how staff can look after themselves

Uptake, effectiveness and safety of COVID-19 vaccines in children and young people in Scotland : protocol for early pandemic evaluation and enhanced surveillance of COVID-19 (EAVE II)

Funding: This research is part of the Data and Connectivity National Core Study, led by Health Data Research UK in partnership with the Office for National Statistics and funded by UK Research and Innovation (grant ref MC_PC_20058). SVK acknowledges funding from a NRS Senior Clinical Fellowship (SCAF/15/02), the Medical Research Council (MC_UU_00022/2) and the Scottish Government Chief Scientist Office (SPHSU17).Background The dynamics of acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission and severity of disease among children and young people (CYP) across different settings are of considerable clinical, public health and societal interest. Severe COVID-19 cases, requiring hospitalisations, and deaths have been reported in some CYP suggesting a need to extend vaccinations to these age groups. As part of the ongoing Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II) study, we aim to investigate the uptake, effectiveness and safety of COVID-19 vaccines in children and young people (CYP) aged 0 to 17 years in Scotland. Specifically, we will estimate: (i) uptake of vaccines against COVID-19, (ii) vaccine effectiveness (VE) against the outcomes of symptomatic SARS-CoV-2 infection, hospitalisation, intensive care unit (ICU) admissions, and death; (iii) VE for first/second dose timing among different age groups and risk groups; and (iv) the safety of vaccines. Methods and analysis We will conduct an open prospective cohort study classifying exposure as time-varying. We will compare outcomes amongst first dose vaccinated and second dose vaccinated CYP to those not yet vaccinated. A Test Negative Design (TND) case control study will be nested within this national cohort to investigate VE against symptomatic infection. The primary outcomes will be (i) uptake of vaccines against COVID-19, (ii) time to COVID-19 infection, hospitalisation, ICU admissions or death, and (iii) adverse events related to vaccines. Vaccination status (unvaccinated, one dose and two doses) will be defined as a time-varying exposure. Data from multiple sources will be linked using a unique identifier. We will conduct descriptive analyses to explore trends in vaccine uptake, and association between different exposure variables and vaccine uptake will be determined using multivariable logistic regression models. VE will be assessed from time-dependent Cox models or Poisson regression models, adjusted for relevant confounders, including age, sex, socioeconomic status, and comorbidities. We will employ self-controlled study designs to determine the risk of adverse events following COVID-19 vaccination. Ethics and dissemination Ethics approval was obtained from the National Research Ethics Committee, South East Scotland 02. We will present findings of this study at international conferences, in peer-reviewed journals and to policy-makers.Publisher PDFPeer reviewe