187 research outputs found
East-West Center Oral History Project : Arjumand Faisel
Full text linkInterviewed by Dan Berman, March 30, 2006 in Islamabad, Pakistan.For more about the East-West Center, see https://www.eastwestcenter.org/Arjumand Faisel had been an actor, TV anchorman and talent manager before age 20. He was already a family physician and senior instructor at Aga Khan University Medical College in Karachi when he came to EWC in 1987 as a Masters in Public Health grantee in Open Grants. His EWC experience in public health training changed his career "from seeing patients to seeing populations and worrying about them."Click on the PDFs to read more. Includes photograph, interview quotes, and the full interview narrative
Soluble CD40 receptor is a biomarker of the burden of carotid artery atherosclerosis in subjects at high cardiovascular risk
Full text linkBACKGROUND AND AIMS: The severity of the atherosclerotic burden is hardly quantifiable in subjects at high cardiovascular (CV) risk under intensive pharmacological therapy. Several molecules have been proposed as circulating biomarkers of atherosclerosis, but none has emerged as clinically meaningful.METHODS: Circulating proteins involved in inflammation, plaque remodeling, smooth muscle cell migration, apoptosis and endothelial activity were measured by Proximity Extension Assay in the SUMMIT study cohort (n = 1500), including patients with type 2 diabetes (66%) and established CV disease (50%), who underwent ultrasound assessment of carotid atherosclerosis with total plaque area quantification.RESULTS: In patients with evidence of carotid artery atherosclerosis (n = 1174), seven biomarkers were identified as the more closely related to atherosclerosis extension. Compared with a multivariable model including major traditional CV risk factors, the percentage gain of explained variability in total plaque area was the greatest (33%) after inclusion of CD40 receptor (CD40R) ligand, followed by PDGF (30%), CD40R (26%), EGF (22%), CXCL1 (15%), HBEGF and MMP-17 (both 11%). The relationship of total plaque area with CD40R, PDGF was hyperbolic. In the whole study cohort, including subjects without carotid plaques, CD40R was the strongest predictor of the presence and extension of carotid atherosclerosis. Subjects in the third CD40R tertile had a more than two-fold greater atherosclerotic burden compared with lower CD40R tertiles, despite an only marginally higher load of CV risk factors.CONCLUSIONS: CD40R stands among an extended set of plausible atherosclerosis-related biomarkers as the most powerful predictor of carotid atherosclerosis burden in a high CV risk cohort
Predictive Role of Atherosclerosis Biomarkers on Carotid Plaque Extension in Type 2 Diabetes
No full textCirculating soluble IL-6 receptor associates with plaque inflammation but not with atherosclerosis severity and cardiovascular risk
Full text linkBackground: The residual cardiovascular risk in subjects receiving guideline-recommended therapy is related to persistent vascular inflammation and IL-6 represents a target for its treatment. IL-6 binds to receptors on leukocytes and hepatocytes and/or by forming complexes with soluble IL-6 receptors (sIL-6R) binding to gp130 which is present on all cells. Here we aimed to estimate the associations of these two pathways with risk of cardiovascular disease (CVD).Methods: IL-6 and sIL-6R were analyzed using the proximity extension assay. Baseline plasma samples were obtained from participants in the prospective Malmö Diet and Cancer (MDC) study (n = 4661), the SUMMIT VIP study (n = 1438) and the Carotid Plaque Imaging Project (CPIP, n = 285). Incident clinical events were obtained through national registers. Plaques removed at surgery were analyzed by immunohistochemistry and biochemical methods.Results: During 23.1 ± 7.0 years follow-up, 575 subjects in the MDC cohort suffered a first myocardial infarction. Subjects in the highest tertile of IL-6 had an increased risk compared to the lowest tertile (HR and 95% CI 2.60 [2.08-3.25]). High plasma IL-6 was also associated with more atherosclerosis, increased arterial stiffness, and impaired endothelial function in SUMMIT VIP, but IL-6 was only weakly associated with plaque inflammation in CPIP. sIL-6R showed no independent association with risk of myocardial infarction, atherosclerosis severity or vascular function, but was associated with plaque inflammation.Conclusions: Our findings show that sIL-6R is a poor marker of CVD risk and associated vascular changes. However, the observation that sIL-6R reflects plaque inflammation highlights the complexity of the role of IL-6 in CVD.</p
Plasma levels of PRO-C3, a type III collagen synthesis marker, are associated with arterial stiffness and increased risk of cardiovascular death
Full text linkBackground and aims: The N-terminal propeptide of type III collagen (PRO-C3) assay measures a pro-peptide released during type III collagen synthesis, an important feature of arterial stiffening and atherogenesis. There is a clinical need for improved non-invasive, cheap and easily accessible methods for evaluating individuals at risk of cardiovascular disease (CVD). In this study, we investigate the potential of using circulating levels of PRO-C3 to mark the degree of vascular stenosis and risk of cardiovascular events. Methods: Baseline plasma levels of PRO-C3 were measured by ELISA in subjects belonging to the SUrrogate markers for Micro- and Macro-vascular hard endpoints for Innovative diabetes Tools (SUMMIT) cohort (N = 1354). Associations between PRO-C3 levels with vascular characteristics, namely stiffness and stenosis, and risk of future cardiovascular events were explored. Subjects were followed up after a median of 35 months (interquartile range 34–36 months), with recorded outcomes cardiovascular death and all-cause mortality. Results: We found a correlation between PRO-C3 levels and pulse wave velocity (rho 0.13, p = 0.000009), a measurement of arterial stiffness. Higher PRO-C3 levels were also associated with elevated blood pressure (rho 0.07, p = 0.014), as well as risk of cardiovascular mortality over a three-year follow-up period (OR 1.56, confidence interval 1.008–2.43, p = 0.046). Conclusions: Elevated circulating PRO-C3 levels are associated with arterial stiffness and future cardiovascular death, in the SUMMIT cohort, suggesting a potential value of PRO-C3 as a novel marker for declining vascular health.</p
Soluble CD40 levels in plasma are associated with cardiovascular disease and in carotid plaques with a vulnerable phenotype
Full text linkBackground and Purpose CD40 and CD40 ligand (CD40L) are costimulatory molecules of the tumor necrosis factor receptor superfamily and well known for their involvement in inflammatory diseases: atherosclerotic mouse models with disrupted CD40 signalling develop lesions of reduced size with a more stable plaque profile. This study investigated the potential of plasma and intraplaque levels of CD40 and CD40L as markers for cardiovascular disease (CVD) in humans and their association with plaque stability. Methods Soluble CD40 and CD40L (sCD40L) were measured in plasma in 1,437 subjects from The SUrrogate markers for Micro-and Macro-vascular hard endpoints for Innovative diabetes Tools (SUMMIT) cohort. Intra-plaque levels of sCD40 and sCD40L were measured in atherosclerotic plaque homogenates from 199 subjects of the Carotid Plaque Imaging Project (CPIP) cohort. Results Both plasma sCD40 and sCD40L levels were elevated in individuals with prevalent stroke, while sCD40 levels also were higher in individuals with a prior acute myocardial infarction. Plasma levels of sCD40 correlated with carotid intima-media thickness and total carotid plaque area and were associated with risk of cardiovascular events over a 3-year follow-up period. Intra-plaque levels of sCD40 and sCD40L were associated with plaque components characteristic for plaque vulnerability and extracellular matrix remodelling. Conclusions Higher plasma sCD40 and sCD40L levels are associated with prevalent CVD. Plasma sCD40 levels also correlate with the severity of carotid atherosclerosis and predict future cardiovascular events, while intra-plaque levels correlate with a vulnerable plaque phenotype. Our findings thus demonstrate that elevated levels of sCD40 and sCD40L are markers of CVD.</p
A Survey on CubeSat Missions and Their Antenna Designs
Full text linkCubeSats are a class of miniaturized satellites that have become increasingly popular in academia and among hobbyists due to their short development time and low fabrication cost. Their compact size, lightweight characteristics, and ability to form a swarm enables them to communicate directly with one another to inspire new ideas on space exploration, space-based measurements, and implementation of the latest technology. CubeSat missions require specific antenna designs in order to achieve optimal performance and ensure mission success. Over the past two decades, a plethora of antenna designs have been proposed and implemented on CubeSat missions. Several challenges arise when designing CubeSat antennas such as gain, polarization, frequency selection, pointing accuracy, coverage, and deployment mechanisms. While these challenges are strongly related to the restrictions posed by the CubeSat standards, recently, researchers have turned their attention from the reliable and proven whip antenna to more sophisticated antenna designs such as antenna arrays to allow for higher gain and reconfigurable and steerable radiation patterns. This paper provides a comprehensive survey of the antennas used in 120 CubeSat missions from 2003 to 2022 as well as a collection of single-element antennas and antenna arrays that have been proposed in the literature. In addition, we propose a pictorial representation of how to select an antenna for different types of CubeSat missions. To this end, this paper aims is to serve both as an introductory guide on CubeSats antennas for CubeSat enthusiasts and a state of the art for CubeSat designers in this ever-growing field
Reservoir-Excess Pressure Parameters Independently Predicts Cardiovascular Events in Individuals With Type 2 Diabetes
Full text linkThis is the author accepted manuscript. The final version is available from the American Heart Association via the DOI in this recordThe parameters derived from reservoir-excess pressure analysis have prognostic utility in several populations. However, evidence in type 2 diabetes (T2DM) remains scarce. We determined if these parameters were associated with T2DM and whether they would predict cardiovascular events in individuals with T2DM. We studied 306 people with T2DM with cardiovascular disease (CVD; DMCVD, 70.4±7.8 years), 348 people with T2DM but without CVD (diabetes mellitus, 67.7±8.4 years), and 178 people without T2DM or CVD (control group [CTRL], 67.2±8.9 years). Reservoir-excess pressure analysis–derived parameters, including reservoir pressure integral, peak reservoir pressure, excess pressure integral, systolic rate constant, and diastolic rate constant, were obtained by radial artery tonometry. Reservoir pressure integral was lower in DMCVD diabetes mellitus and than CTRL. Peak reservoir pressure was lower, and excess pressure integral was greater in DMCVD diabetes mellitus than and CTRL. Systolic rate constant was lower in a stepwise manner among groups (DMCVD< diabetes mellitus <CTRL). Diastolic rate constant was greater in DMCVD than CTRL. In the subgroup of individuals with T2DM (n=642), 14 deaths (6 cardiovascular and 9 noncardiovascular causes), and 108 cardiovascular events occurred during a 3-year follow-up period. Logistic regression analysis revealed that reservoir pressure integral (odds ratio, 0.59 [95% CI, 0.45–0.79]) and diastolic rate constant (odds ratio, 1.60 [95% CI, 1.25–2.06]) were independent predictors of cardiovascular events during follow-up after adjusting for conventional risk factors (both P<0.001). Further adjustments for potential confounders had no influence on associations. These findings demonstrate that altered reservoir-excess pressure analysis–derived parameters are associated with T2DM. Furthermore, baseline values of reservoir pressure integral and diastolic rate constant independently predict cardiovascular events in individuals with T2DM, indicating the potential clinical utility of these parameters for risk stratification in T2DM.European Union FP7National Institute for Health Research (NIHR
Assessment of endothelial function as a marker of cardiovascular risk in patients with rheumatoid arthritis
No full textThe endothelium is a major regulator of cardiovascular function and maintains an atheroprotective role through several mechanisms, including vasodilatation, inhibition of platelet aggregation, having anticoagulant and profibrinolytic effects, and having an anti-inflammatory effect. Early changes in the normal functioning of the endothelium are key initiating factors in the development and progression of atherosclerosis. These changes are present well before the presentation of clinical symptoms. Thus, researchers have focused much attention on developing methods for reliable non-invasive testing of endothelial function to allow early detection and monitoring and progression of subclinical atherosclerosis. To date, there is a wide range of methods in use to assess endothelial function, each with its own advantages and limitations. Ideally, the tests should be non-invasive to allow repeated measurements and be applicable in normal healthy subjects and also in children. Given the wide range of regulatory functions of the endothelium, it is not surprising that there is no single measure of endothelial function that provides all the necessary information regarding vascular integrity in different vascular beds. Therefore, a combination of tests examining different components of the vascular system is more appropriate. Since patients with rheumatoid arthritis have increased mortality due to cardiovascular disease, assessment of endothelial function could prove to be useful tools in the identification and monitoring of cardiovascular risk. The purpose of this review is to give a brief overview of some of the commonly used techniques for assessment of endothelial function, and in particular on those that have been used in studies of patients with rheumatoid arthritis.</p
Commentary on viewpoint:the human cutaneous circulation as a model of generalized microvascular function
No full text- …
