30 research outputs found
Smooth muscle enriched long non-coding RNA (SMILR) regulates cell proliferation
BackgroundâPhenotypic switching of vascular smooth muscle cells from a contractile to a synthetic state is implicated in diverse vascular pathologies, including atherogenesis, plaque stabilization, and neointimal hyperplasia. However, very little is known about the role of long noncoding RNA (lncRNA) during this process. Here, we investigated a role for lncRNAs in vascular smooth muscle cell biology and pathology.
Methods and ResultsâUsing RNA sequencing, we identified >300 lncRNAs whose expression was altered in human saphenous vein vascular smooth muscle cells following stimulation with interleukin-1α and platelet-derived growth factor. We focused on a novel lncRNA (Ensembl: RP11-94A24.1), which we termed smooth muscleâinduced lncRNA enhances replication (SMILR). Following stimulation, SMILR expression was increased in both the nucleus and cytoplasm, and was detected in conditioned media. Furthermore, knockdown of SMILR markedly reduced cell proliferation. Mechanistically, we noted that expression of genes proximal to SMILR was also altered by interleukin-1α/platelet-derived growth factor treatment, and HAS2 expression was reduced by SMILR knockdown. In human samples, we observed increased expression of SMILR in unstable atherosclerotic plaques and detected increased levels in plasma from patients with high plasma C-reactive protein.
ConclusionsâThese results identify SMILR as a driver of vascular smooth muscle cell proliferation and suggest that modulation of SMILR may be a novel therapeutic strategy to reduce vascular pathologies
F-Fluoride and F-Fluorodeoxyglucose Positron Emission Tomography After Transient Ischemic Attack or Minor Ischemic Stroke: Case-Control Study.
BACKGROUND: Combined positron emission tomography (PET) and computed tomography (CT) can assess both anatomy and biology of carotid atherosclerosis. We sought to assess whether F-fluoride or F-fluorodeoxyglucose can identify culprit and high-risk carotid plaque.
METHODS AND RESULTS: We performed F-fluoride and F-fluorodeoxyglucose PET/CT in 26 patients after recent transient ischemic attack or minor ischemic stroke: 18 patients with culprit carotid stenosis awaiting carotid endarterectomy and 8 controls without culprit carotid atheroma. We compared standardized uptake values in the clinically adjudicated culprit to the contralateral asymptomatic artery, and assessed the relationship between radiotracer uptake and plaque phenotype or predicted cardiovascular risk (ASSIGN score [Assessing Cardiovascular Risk Using SIGN Guidelines to Assign Preventive Treatment]). We also performed micro PET/CT and histological analysis of excised plaque. On histological and micro PET/CT analysis, F-fluoride selectively highlighted microcalcification. Carotid F-fluoride uptake was increased in clinically adjudicated culprit plaques compared with asymptomatic contralateral plaques (log standardized uptake value 0.29±0.10 versus 0.23±0.11, P=0.001) and compared with control patients (log standardized uptake value 0.29±0.10 versus 0.12±0.11, P=0.001). F-Fluoride uptake correlated with high-risk plaque features (remodeling index [r=0.53, P=0.003], plaque burden [r=0.51, P=0.004]), and predicted cardiovascular risk [r=0.65, P=0.002]). Carotid F-fluorodeoxyglucose uptake appeared to be increased in 7 of 16 culprit plaques, but no overall differences in uptake were observed in culprit versus contralateral plaques or control patients. However, F-fluorodeoxyglucose did correlate with predicted cardiovascular risk (r=0.53, P=0.019), but not with plaque phenotype.
CONCLUSIONS: F-Fluoride PET/CT highlights culprit and phenotypically high-risk carotid plaque. This has the potential to improve risk stratification and selection of patients who may benefit from intervention.Dr Vesey and the study were funded by program grants from the British Heart Foundation (PG12/8/29371) and Chest Heart and Stroke Scotland (R13/A147). Dr Jenkins, Vesey, Dweck, and Newby are supported by the British Heart Foundation (FS/14/78/31020, CH/09/002) and the Wellcome Trust (WT103782AIA). Dr Dweck is the recipient of the Sir Jules Thorn Biomedical Research Award 2015. The Wellcome Trust Clinical Research Facility and the Clinical Research Imaging Centre are supported by National Health Service (NHS) Research Scotland (NRS) through NHS Lothian. Dr Beek is supported by the Scottish Imaging Networkâa Platform of Scientific Excellence (SINAPSE). Dr Rudd is part-supported by the National Institute for Health Research Cambridge Biomedical Research Centre, the British Heart Foundation, and the Wellcome Trust
REPAIRS Delphi: A UK and Ireland Consensus Statement on the Management of Infected Arterial Pseudoaneurysms Secondary to Groin Injecting Drug Use
\ua9 2024 The Author(s)Objective: Consensus guidelines on the optimal management of infected arterial pseudoaneurysms secondary to groin injecting drug use are lacking. This pathology is a problem in the UK and globally, yet operative management options remain contentious. This study was designed to establish consensus to promote better management of these patients, drawing on the expert experience of those in a location with a high prevalence of illicit drug use. Methods: A three round modified Delphi was undertaken, systematically surveying consultant vascular surgeons in the UK and Ireland using an online platform. Seventy five vascular surgery units were invited to participate, with one consultant providing the unit consensus practice. Round one responses were thematically analysed to generate statements for round two. These statements were evaluated by participants using a five point Likert scale. Consensus was achieved at a threshold of 70% or more agreement or disagreement. Those statements not reaching consensus were assessed and modified for round three. The results of the Delphi process constituted the consensus statement. Results: Round one received 64 (86%) responses, round two 59 (79%) responses, and round three 62 (83%) responses; 73 (97%) of 75 units contributed. Round two comprised 150 statements and round three 24 statements. Ninety one statements achieved consensus agreement and 15 consensus disagreement. The Delphi statements covered sequential management of these patients from diagnosis and imaging, antibiotics and microbiology, surgical approach, wound management, follow up, and additional considerations. Pre-operative imaging achieved consensus agreement (97%), with computerised tomography angiography being the modality of choice (97%). Ligation and debridement without arterial reconstruction was the preferred approach at initial surgical intervention (89%). Multidisciplinary management, ensuring holistic care and access to substance use services, also gained consensus agreement. Conclusion: This comprehensive consensus statement provides a strong insight into the standard of care for these patients
Carotid artery volumetric measures associate with clinical ten-year cardiovascular (CV) risk scores and individual traditional CV risk factors in rheumatoid arthritis; a carotid-MRI feasibility study
Background: Common carotid artery intima-media thickness (CIMT), as measured by ultrasound, has utility in stratification of the accelerated cardiovascular risk seen in rheumatoid arthritis (RA); however, the technique has limitations. Carotid magnetic resonance imaging (MRI) is emerging as a useful research tool in the general population, but has yet to be applied in RA populations. Our objectives were to describe the utility of carotid artery MRI (carotid-MRI) in patients with RA in comparison to healthy controls and to describe the association with RA disease phenotype.
Methods: Sixty-four patients with RA and no history of cardiovascular (CV) disease/diabetes mellitus were assessed for RA and CV profile, including homeostasis model assessment-estimated insulin resistance (HOMA-IR) and N-terminal pro-brain natriuretic peptide (NT-proBNP). All underwent carotid-MRI (3 T), and were compared to 24 healthy controls. Univariable analysis (UVA) and multivariable linear regression models (MVA) were used to determine associations between disease phenotype and carotid-MRI measures.
Results: There were no significant differences in carotid arterial wall measurements between patients with RA and controls. Wall and luminal volume correlated with 10-year CV risk scores (adjusted as per 2017 European League Against Rheumatism (EULAR) guidance); rhoâ=â0.33 (pâ=â0.012) and rhoâ=â0.35 (pâ=â0.008), respectively, for Joint British Societies-2 risk score. In UVA, carotid-MRI volumetric measures predominantly were associated with traditional CV risk factors including age, ever-smoking and HOMA-IR (pâ<â0.05). Lower body mass index was associated with wall maximum thickness (râ=âââ0.25 pâ=â0.026). In MVA, age was independently associated with wall volume (B 1.13 (95% CI 0.32, 1.93), pâ=â0.007) and luminal volume (B 3.69 (95% CI 0.55, 6.83, pâ=â0.022), and RA disease duration was associated with luminal volume (B 3.88 (95% CI 0.80, 6.97), pâ=â0.015).
Conclusions: This study demonstrates the utility of carotid-MRI in RA, reporting an association between three-dimensional measures in particular and CV risk scores, individual traditional CV risk factors and RA disease duration. Carotid-MRI in RA is a promising research tool in the investigation of CVD
Myocardial fibrosis and cardiac decompensation in aortic stenosis
OBJECTIVES: Cardiac magnetic resonance (CMR) was used to investigate the extracellular compartment and myocardial fibrosis in patients with aortic stenosis, as well as their association with other measures of left ventricular decompensation and mortality. BACKGROUND: Progressive myocardial fibrosis drives the transition from hypertrophy to heart failure in aortic stenosis. Diffuse fibrosis is associated with extracellular volume expansion that is detectable by T1 mapping, whereas late gadolinium enhancement (LGE) detects replacement fibrosis. METHODS: In a prospective observational cohort study, 203 subjects (166 with aortic stenosis [69 years; 69% male]; 37 healthy volunteers [68 years; 65% male]) underwent comprehensive phenotypic characterization with clinical imaging and biomarker evaluation. On CMR, we quantified the total extracellular volume of the myocardium indexed to body surface area (iECV). The iECV upper limit of normal from the control group (22.5 ml/m(2)) was used to define extracellular compartment expansion. Areas of replacement mid-wall LGE were also identified. All-cause mortality was determined during 2.9 ± 0.8 years of follow up. RESULTS: iECV demonstrated a good correlation with diffuse histological fibrosis on myocardial biopsies (r = 0.87; p < 0.001; n = 11) and was increased in patients with aortic stenosis (23.6 ± 7.2 ml/m(2) vs. 16.1 ± 3.2 ml/m(2) in control subjects; p < 0.001). iECV was used together with LGE to categorize patients with normal myocardium (iECV <22.5 ml/m(2); 51% of patients), extracellular expansion (iECV â„22.5 ml/m(2); 22%), and replacement fibrosis (presence of mid-wall LGE, 27%). There was evidence of increasing hypertrophy, myocardial injury, diastolic dysfunction, and longitudinal systolic dysfunction consistent with progressive left ventricular decompensation (all p < 0.05) across these groups. Moreover, this categorization was of prognostic value with stepwise increases in unadjusted all-cause mortality (8 deaths/1,000 patient-years vs. 36 deaths/1,000 patient-years vs. 71 deaths/1,000 patient-years, respectively; p = 0.009). CONCLUSIONS: CMR detects ventricular decompensation in aortic stenosis through the identification of myocardial extracellular expansion and replacement fibrosis. This holds major promise in tracking myocardial health in valve disease and for optimizing the timing of valve replacement. (The Role of Myocardial Fibrosis in Patients With Aortic Stenosis; NCT01755936)