A.M. Devlin

Gene transfer of endothelial nitric oxide synthase improves nitric oxide-dependent endothelial function in a hypertensive rat model.

OBJECTIVE We have shown previously that there is a relative nitric oxide deficiency at the level of vascular endothelium in the stroke-prone spontaneously hypertensive rat (SHRSP), a model of human essential hypertension, as compared to its normotensive reference strain Wistar Kyoto (WKY) rat. The aim of the current study was to investigate whether adenoviral-mediated gene transfer of an endothelial nitric oxide synthase (eNOS) cDNA (AdCMVeNOS) into carotid arteries of the SHRSP may improve endothelial function. METHODS Enzyme activity of the recombinant eNOS protein encoded by AdCMVeNOS was tested using a Griess assay in endothelial cells in culture. Left carotid arteries of SHRSP were surgically isolated and exposed to either the AdCMVeNOS or control beta-galactosidase-containing virus, (2 x 10(9) pfu/ml) ex vivo and in vivo. The vessels were harvested 24 h after surgery and analysed by Western blotting, immunohistochemistry and by examining endothelial function ex vivo. RESULTS Cultured endothelial cells showed almost 100% transduction with both viruses and a dose response of eNOS expression showed a five-fold increase in nitrite production for AdCMVeNOS with no change for beta-galactosidase-containing virus. Western blotting demonstrated a significant increase of eNOS expression in vessels infused with AdCMVeNOS when compared to controls. Immunohistochemistry showed highly positive staining with monoclonal antibodies against eNOS in the intact endothelial cells of the AdCMVeNOS infused vessels. The areas under the curve of the concentration responses to phenylephrine (10(-9) to 3 x 10(-6) M) in the absence and presence of NG-nitroarginine methyl ester (100 microM) showed increased basal nitric oxide bioavailability in the carotid arteries infused with AdCMVeNOS compared to the control (n = 6 for each; P = 0.0069; 95% CI, 0.864 to 3.277). CONCLUSIONS Our results show that AdCMVeNOS is an effective tool for vascular gene transfer and that it can improve endothelial NO availability in the SHRSP, a genetic model of essential hypertension and endothelial dysfunction.

Vascular smooth muscle cell polyploidy and cardiomyocyte hypertrophy due to chronic NOS inhibition in vivo

To assess the vascular and cardiac response to NO (nitric oxide) synthase (NOS) blockade in vivo, Wistar-Kyoto rats (WKY) were treated for 3 wk with N G-nitro-l-arginine methyl ester (l-NAME; 10 mg ⋅ kg-1 ⋅ day-1).l-NAME treatment induced hypertension that was associated with increased plasma renin activity. Flow cytometry cell cycle DNA analysis showed that aortic vascular smooth muscle cells (VSMC) froml-NAME-treated WKY had a significantly higher polyploid population compared with WKY controls. Using organ bath experiments, we have shown that aortic rings froml-NAME-treated WKY have an increased contractile response to phenylephrine and impaired relaxation to carbachol compared with control rings. NOS blockade in vivo caused a significant increase in cardiac and left ventricular hypertrophy. Northern mRNA analysis of the myocardium showed thatl-NAME treatment caused reexpression of the fetal skeletal α-actin isoform without alterations in collagen type I expression, a pattern indicating true hypertrophy of the cardiomyocytes. These studies provide further insight to confirm that NO deficiency in vivo results in the development of vascular and cardiac hypertrophy.

The effects of perindopril on vascular smooth muscle polyploidy in stroke-prone spontaneously hypertensive rats

Objective To quantify vascular smooth muscle polyploidy and growth kinetics in aortic cells from stroke-prone spontaneously hypertensive rats (SHRSP) and from normotensive Wistar-Kyoto (WKY) rats, and to examine the effects of treatment with the angiotensin converting enzyme (ACE) inhibitor perindopril on these parameters. Design The following experimental groups were used: young (age <20 weeks) and old (age > 20 weeks) untreated WKY rats and untreated SHRSP; SHRSP treated with perindopril, and age- and sex-matched control SHRSP; and SHRSP treated with hydralazine and hydrochlorothiazide and age- and sex-matched control SHRSP. The effects of treatment of the SHRSP with perindopril for 30 days on vascular smooth muscle polyploidy and growth kinetics were measured and compared with the effects of equivalent antihypertensive doses of hydralazine and hydrochlorothiazide. Methods Vascular smooth muscle polyploidy was measured using flow-cytometry DNA analysis of freshly harvested cells. Growth curves were performed on cultured aortic cells. Plasma renin activity was measured by an antibody-trapping method, plasma angiotensin II (Ang II) by radioimmunoassay and plasma ACE activity by a colorimetric method. Cardiac hypertrophy was evaluated by measuring the heart weight: body weight and left ventricle + septum weight: body weight ratios. Results The SHRSP had markedly and significantly elevated G2 + M phase of the cell cycle. Treatment with perindopril resulted in a significant reduction in polyploidy in the SHRSP, whereas treatment with hydralazine and hydrochlorothiazide had no effect on the percentage of cells in the G2 + M phase of the cell cycle. The regression of polyploidy after treatment with perindopril was associated with a significant reduction in the concentration of Ang II and ACE activity, and with a significant regression of cardiac hypertrophy. Increased mitogenesis of cultured vascular smooth muscle cells from the SHRSP was not altered by treatment with perindopril. Conclusions ACE inhibition reduces vascular smooth muscle polyploidy in large conduit arteries. This type of vascular protection is mediated by the reduced Ang II and possibly by increased kinins level, rather than by the hypotensive effect alone.

Delivering Digital Health and Well-Being at Scale: Lessons Learned during the Implementation of the dallas Program in the United Kingdom

Abstract Objective To identify implementation lessons from the United Kingdom Delivering Assisted Living Lifestyles at Scale (dallas) program—a large-scale, national technology program that aims to deliver a broad range of digital services and products to the public to promote health and well-being. Materials and Methods Prospective, longitudinal qualitative research study investigating implementation processes. Qualitative data collected includes semi-structured e-Health Implementation Toolkit–led interviews at baseline/mid-point ( n = 38), quarterly evaluation, quarterly technical and barrier and solutions reports, observational logs, quarterly evaluation alignment interviews with project leads, observational data collected during meetings, and ethnographic data from dallas events ( n > 200 distinct pieces of qualitative data). Data analysis was guided by Normalization Process Theory, a sociological theory that aids conceptualization of implementation issues in complex healthcare settings. Results Five key challenges were identified: 1) The challenge of establishing and maintaining large heterogeneous, multi-agency partnerships to deliver new models of healthcare; 2) The need for resilience in the face of barriers and set-backs including the backdrop of continually changing external environments; 3) The inherent tension between embracing innovative co-design and achieving delivery at pace and at scale ; 4) The effects of branding and marketing issues in consumer healthcare settings; and 5) The challenge of interoperability and information governance, when commercial proprietary models are dominant. Conclusions The magnitude and ambition of the dallas program provides a unique opportunity to investigate the macro level implementation challenges faced when designing and delivering digital health and wellness services at scale. Flexibility, adaptability, and resilience are key implementation facilitators when shifting to new digitally enabled models of care.

DNA Synthesis and Apoptosis in Smooth Muscle Cells From a Model of Genetic Hypertension

The present study was designed to assess vascular smooth muscle cell (VSMC) proliferation and apoptosis in primary cultured VSMCs prepared from the aortic tunica media of adult (4 to 5 months old) age- and gender-matched groups of stroke-prone spontaneously hypertensive rats (SHRSP) and the normotensive reference strain, Wistar-Kyoto (WKY) rats. In the present study, VSMC proliferation was assessed with measurement of DNA synthesis in response to stimulation of G(0)/G(1) arrested VSMCs with 10% serum, whereas apoptosis was measured in response to serum deprivation. Apoptosis in aortic VSMCs was assessed in vitro with the technique of Annexin V binding in combination with propidium iodide exclusion with bivariate flow cytometric analysis. The percentage of necrotic VSMCs in the cell populations was assessed simultaneously. The light-scattering properties of the cells were assessed to provide further information on cell shrinkage and chromatin condensation. Results of the present study have shown enhanced DNA synthesis in VSMCs from SHRSP (n=10; 5.2+/-0.9 cpmx10(3)/mg protein) compared with WKY (n=12; 2.4+/-0.7 cpmx10(3) /mg protein; P<0.05, 95% CI, -5271 to -296). In addition, the results of the present study have demonstrated the role of serum in the survival of VSMCs in vitro, because SHRSP VSMCs underwent significantly more apoptosis in response to insult by serum deprivation (n=13; 10.21+/-1.8%) than WKY VSMCs (n=7; 3.44+/-1.4%; P<0.01, 95% CI, -11.5 to -2.0). Thus, it appears that both proliferation and apoptosis are enhanced in synthetic phenotype aortic medial VSMCs from the SHRSP in vitro.

Increased Na(+)/H(+) exchanger isoform 1 activity in spontaneously hypertensive rats: lack of mutations within the coding region of NHE1.

Enhanced Na(+)/H(+) exchange, measured as amiloride derivative-sensitive Na(+) and H(+) fluxes in cells with a preliminary acidified cytoplasm (Deltamu(H+)-induced Na(+)/H(+) exchange), is one of the most prominent intermediate phenotypes of altered vascular smooth muscle cell (VSMC) function in spontaneously hypertensive rats (SHR). Analysis of Na(+)/H(+) exchange in F(2) hybrids of SHR and normotensive rats seems to be the most appropriate approach in the search for the genetic determinants of abnormal activity of this carrier. However, the measurement of Deltamu(H+)-induced Na(+)/H(+) exchange is hardly appropriate for precise analysis of the carriers activity in VSMC derived from several hundred F(2) hybrids. To overcome this problem, we compared the rate of (22)Na influx under baseline conditions and in Na(+)-loaded (ouabain-treated) VSMC. The dose-dependency of the rate of Deltamu(H+)-induced H(+) efflux as well as of (22)Na influx in control and ouabain-treated cells on ethylisopropylamiloride (EIPA) concentration were not different (K(0.5) approximately 0.3 microM), suggesting that these ion transport pathways are mediated by the same carrier. EIPA-sensitive (22)Na influx in Na(+)-loaded cells was approximately 6-fold higher than in ouabain-untreated VSMC and was increased by 50-70% in two different substrains of SHR. About the same increment of EIPA-sensitive (22)Na influx in Na(+)-loaded VSMC was observed in 5- to 6-week-old SHR (an age at which hypertension has not yet developed) as well as in stroke-prone SHR (SHRSP) with severe hypertension, indicating that the heightened activity of Na(+)/H(+) exchange is not a consequence of long-term blood pressure elevation. To examine whether or not the augmented activity of Na(+)/H(+) exchange in SHR is caused by mutation of NHE1, i.e. the only isoform of this carrier expressed in VSMC, we undertook single-stranded conformational polymorphism analysis of 23 NHE1 cDNA fragments from SHR and SHRSP and sequencing of the 456-2421 NHE1 cDNA fragment. This study did not reveal any mutation in the entire coding region of NHE1. The lack of mutation in the coding region of NHE1 indicates that the augmented activity of the ubiquitous Na(+)/H(+) exchanger in primary hypertension is caused by altered regulation of carrier turnover number or/and its plasma membrane content.

Inter-Life: A Novel, Three-Dimensional, Virtual Learning Environment for Life Transition Skills Learning.

This paper presents the findings from one of the first empirical research studies which has investigated the impact of Inter-Life; a novel three-dimensional immersive virtual learning environment, on learning and development of social and educational life transition skills in a group of looked after and accommodated children. Drawing on social constructivism in which meaningful learning is related to context and situated in practice, we report on a series of Inter-Life workshops that enabled young people to work together and through the processes of participation in authentic learning activities contributed to the development of life transition skills such as self-confidence, empathy, negotiation and mediation skills, teamwork and active problem-solving skills. The novel affordances of the Inter-Life virtual world which contributed to the development of the learning community included the ability to personalise learner engagement and activities from the outset along with ‘co-presence’ and ‘immersion’ and the flexibility provided by the innovative, technology-enhanced Inter-Life platform. This study presents some empirical evidence to demonstrate the efficacy of new models of learning that are mediated by innovative malleable technologies that can be shaped by the learner in a participatory manner.

Different effects of antihypertensive agents on cardiac and vascular hypertrophy in the transgenic rat line TGR(mRen2)27.

The hypertensive transgenic rat model TGR(mRen2)27 has been used to investigate the development of cardiac and vascular hypertrophy in response to two different drug regimes. Cardiac hypertrophy was shown to be related to age and gender with the copy number of mouse renin transgenes having an additive effect. A similar observation was noted for hypertrophy in the vasculature, which was assessed using flow cytometry cell cycle DNA analysis of aortic vascular smooth muscle cells. Chronic treatment from weaning with equihypotensive doses of perindopril (2 mg/kg/day) or hydralazine and hydrochlorothiazide (4 mg/day of each) prevented the development of cardiac hypertrophy. Perindopril treatment also effectively prevented the development of vascular hypertrophy; however, treatment with hydralazine and hydrochlorothiazide was not as effective despite equivalent blood pressure reduction. These studies have demonstrated the presence of marked vascular and cardiac hypertrophy in the hypertensive transgenic TGR(mRen2)27 model of hypertension. Furthermore, these results provide new evidence to support the role of a locally activated renin angiotensin system in the blood vessel wall, which is involved in the pathogenesis of vascular hypertrophy in this transgenic rat model.

Visualizing Intercultural Literacy: Engaging Critically with Diversity and Migration in the Classroom through an Image-Based Approach.

Accessible forms of language, learning and literacy, as well as strategies that support intercultural communication are needed for the diverse population of refugee, asylum seeker and migrant children within schools. The research project Journeys from Images to Words explored the potential of visual texts to address these issues. Working in Glasgow primary schools within critical pedagogical frameworks that invite sharing of personal narratives and of cultural knowledge, the researchers examined and evaluated an image-based approach, both for reading and responding to a selection of childrens texts and for obtaining an insight into the home literacy practices of diverse communities. In this article, a ‘generative theme’, as used by Paulo Freire is used to examine how students engaged with reading visual texts, shared their responses and extended their intercultural understanding. The results from this project provide evidence for the inclusion of visual texts and methodologies within critical pedagogies in order to develop intercultural literacy in the classroom.

Readiness for Delivering Digital Health at Scale: Lessons From a Longitudinal Qualitative Evaluation of a National Digital Health Innovation Program in the United Kingdom

Background Digital health has the potential to support care delivery for chronic illness. Despite positive evidence from localized implementations, new technologies have proven slow to become accepted, integrated, and routinized at scale. Objective The aim of our study was to examine barriers and facilitators to implementation of digital health at scale through the evaluation of a £37m national digital health program: ‟Delivering Assisted Living Lifestyles at Scale” (dallas) from 2012-2015. Methods The study was a longitudinal qualitative, multi-stakeholder, implementation study. The methods included interviews (n=125) with key implementers, focus groups with consumers and patients (n=7), project meetings (n=12), field work or observation in the communities (n=16), health professional survey responses (n=48), and cross program documentary evidence on implementation (n=215). We used a sociological theory called normalization process theory (NPT) and a longitudinal (3 years) qualitative framework analysis approach. This work did not study a single intervention or population. Instead, we evaluated the processes (of designing and delivering digital health), and our outcomes were the identified barriers and facilitators to delivering and mainstreaming services and products within the mixed sector digital health ecosystem. Results We identified three main levels of issues influencing readiness for digital health: macro (market, infrastructure, policy), meso (organizational), and micro (professional or public). Factors hindering implementation included: lack of information technology (IT) infrastructure, uncertainty around information governance, lack of incentives to prioritize interoperability, lack of precedence on accountability within the commercial sector, and a market perceived as difficult to navigate. Factors enabling implementation were: clinical endorsement, champions who promoted digital health, and public and professional willingness. Conclusions Although there is receptiveness to digital health, barriers to mainstreaming remain. Our findings suggest greater investment in national and local infrastructure, implementation of guidelines for the safe and transparent use and assessment of digital health, incentivization of interoperability, and investment in upskilling of professionals and the public would help support the normalization of digital health. These findings will enable researchers, health care practitioners, and policy makers to understand the current landscape and the actions required in order to prepare the market and accelerate uptake, and use of digital health and wellness services in context and at scale.