Predicting signatures of anisotropic resonance energy transfer in dye-functionalized nanoparticles

Resonance energy transfer (RET) is an inherently anisotropic process. Even the simplest, well-known F\"orster theory, based on the transition dipole-dipole coupling, implicitly incorporates the anisotropic character of RET. In this theoretical work, we study possible signatures of the fundamental anisotropic character of RET in hybrid nanomaterials composed of a semiconductor nanoparticle (NP) decorated with molecular dyes. In particular, by means of a realistic kinetic model, we show that the analysis of the dye photoluminescence difference for orthogonal input polarizations reveals the anisotropic character of the dye-NP RET which arises from the intrinsic anisotropy of the NP lattice. In a prototypical core/shell wurtzite CdSe/ZnS NP functionalized with cyanine dyes (Cy3B), this difference is predicted to be as large as 75\% and it is strongly dependent in amplitude and sign on the dye-NP distance. We account for all the possible RET processes within the system, together with competing decay pathways in the separate segments. In addition, we show that the anisotropic signature of RET is persistent up to a large number of dyes per NP.Comment: 9 pages, 5 figures. Supplementary information available at http://pubs.rsc.org/en/content/articlelanding/2016/ra/c6ra22433d/unauth#!divAbstrac

Smoking Status and Metabolic Syndrome in the Multi-Ethnic Study of Atherosclerosis. A cross-sectional study.

International audienceABSTRACT: BACKGROUND: Current smoking is associated with type 2 diabetes mellitus and impaired glucose tolerance but its association with the metabolic syndrome (metS), particularly with sufficiently sampled African American representation, has not been clearly established. OBJECTIVE: To assess whether a) metS is associated with smoking; b) any increased risk of metS among smokers is independent of body mass index (BMI) compared with non-smokers; c) smoking status is differentially associated with the metS and its components across different ethnic groups. METHODS: Cross sectional analysis of the Multi-Ethnic Study of Atherosclerosis (MESA) a community population-based sample free of cardiovascular disease. RESULTS: Current smokers (N=769) had higher risk of metS (odds ratio [OR, 95 % confidence interval]: 1.4, 1.1-1.7) versus never (reference, N=2981) and former smokers (1.0, 0.8-1.1, N=2163) and for metS components: high waist circumference (WC) (OR:1.9, 1.2-2.1), low high density lipoprotein cholesterol (HDL-C) (1.5, 1.3-1.8), elevated plasma triglycerides (TG) (OR:1.4, 1.2-1.7) as well as high C-reactive protein (CRP, an inflammatory marker) concentration (OR: 1.6,1.3-2.0) compared to never and former smokers after adjustment for BMI. A smoking status by ethnicity interaction occurred such that African American current and former smokers had greater likelihood of low HDL-C than White counterparts. CONCLUSIONS: This study found that smoking is associated with the metS and despite the lower BMI of current smokers the prevalence of low HDL-C, elevated TG and CRP is higher among them than among non-smokers. African American individuals generally have higher HDL-C than Whites but smoking wipes out this advantage

Acculturation is associated with left ventricular mass in a multiethnic sample: the Multi-Ethnic Study of Atherosclerosis.

BackgroundAcculturation involves stress-related processes and health behavioral changes, which may have an effect on left ventricular (LV) mass, a risk factor for cardiovascular disease (CVD). We examined the relationship between acculturation and LV mass in a multiethnic cohort of White, African-American, Hispanic and Chinese subjects.MethodsCardiac magnetic resonance assessment was available for 5004 men and women, free of clinical CVD at baseline. Left ventricular mass index was evaluated as LV mass indexed by body surface area. Acculturation was characterized based on language spoken at home, place of birth and length of stay in the United States (U.S.), and a summary acculturation score ranging from 0 = least acculturated to 5 = most acculturated. Mean LV mass index adjusted for traditional CVD risk factors was compared across acculturation levels.ResultsUnadjusted mean LV mass index was 78.0 ± 16.3 g/m(2). In adjusted analyses, speaking exclusively English at home compared to non-English language was associated with higher LV mass index (81.3 ± 0.4 g/m(2) vs 79.9 ± 0.5 g/m(2), p = 0.02). Among foreign-born participants, having lived in the U.S. for ≥ 20 years compared to < 10 years was associated with greater LV mass index (81.6 ± 0.7 g/m(2) vs 79.5 ± 1.1 g/m(2), p = 0.02). Compared to those with the lowest acculturation score, those with the highest score had greater LV mass index (78.9 ± 1.1 g/m(2) vs 81.1 ± 0.4 g/m(2), p = 0.002). There was heterogeneity in which measure of acculturation was associated with LV mass index across ethnic groups.ConclusionsGreater acculturation is associated with increased LV mass index in this multiethnic cohort. Acculturation may involve stress-related processes as well as behavioral changes with a negative effect on cardiovascular health

Ambulatory blood pressure monitoring phenotypes among individuals with and without diabetes taking antihypertensive medication: the Jackson Heart Study

Ambulatory blood pressure monitoring (ABPM) can detect phenotypes associated with increased cardiovascular disease (CVD) risk. Diabetes is associated with increased CVD risk but few data are available documenting whether blood pressure (BP) phenotypes, detected by ABPM, differ between individuals with versus without diabetes. We conducted a cross-sectional analysis of 567 participants in the Jackson Heart Study, a population-based study of African Americans, taking antihypertensive medication to evaluate the association between diabetes and ABPM phenotypes. Two clinic BP measurements were taken at baseline following a standardized protocol. ABPM was performed for 24 h following the clinic visit. ABPM phenotypes included daytime, sustained, nocturnal and isolated nocturnal hypertension, a non-dipping BP pattern, and white coat, masked and masked isolated nocturnal hypertension. Diabetes was defined as fasting glucose greater than or equal to126 mg dl−1, haemoglobin A1c greater than or equal to6.5% (48 mmol mol−1) or use of insulin or oral hypoglycaemic medications. Of the included participants (mean age 62.3 years, 71.8% female), 196 (34.6%) had diabetes. After multivariable adjustment, participants with diabetes were more likely to have daytime hypertension (prevalence ratio (PR): 1.32; 95% confidence interval (CI): 1.09–1.60), masked hypertension (PR: 1.46; 95% CI: 1.11–1.93) and masked isolated nocturnal hypertension (PR: 1.39; 95% CI: 1.02–1.89). Although nocturnal hypertension was more common among participants with versus without diabetes, this association was not present after adjustment for daytime systolic BP. Diabetes was not associated with the other ABPM phenotypes investigated. This study highlights the high prevalence of ABPM phenotypes among individuals with diabetes taking antihypertensive medication

Immigrant status and cardiovascular risk over time: results from the Multi-Ethnic Study of Atherosclerosis

Despite cross-sectional evidence that foreign-born United States (US) residents often have better health than US-born residents of similar race/ethnicity, we know little about overall cardiovascular risk progression over time among immigrants as they age in the US

Relationship of Metabolic Syndrome With Incident Aortic Valve Calcium and Aortic Valve Calcium Progression: The Multi-Ethnic Study of Atherosclerosis (MESA)*

ObjectiveMetabolic syndrome (MetS) has been associated with increased prevalence of aortic valve calcium (AVC) and with increased progression of aortic stenosis. The purpose of this study was to determine whether MetS is associated with increased risks for the development of new ("incident") AVC or for progression of established AVC as assessed by CT.Research design and methodsThe relationships of MetS or its components as well as of diabetes to risks for incident AVC or AVC progression were studied among participants with CT scans performed at baseline and at either year 2 or year 3 examinations in the Multi-Ethnic Study of Atherosclerosis (MESA).ResultsOf 5,723 MESA participants meeting criteria for inclusion, 1,674 had MetS by Adult Treatment Panel III criteria, whereas 761 had diabetes. Among the 5,123 participants without baseline AVC, risks for incident AVC, adjusted for time between scans, age, sex, race/ethnicity, LDL cholesterol, lipid-lowering medications, and smoking, were increased significantly for MetS (odds ratio [OR] 1.67 [95% CI 1.21-2.31]) or diabetes (2.06 [1.39-3.06]). In addition, there was an increase in incident AVC risk with increasing number of MetS components. Similar results were found using the International Diabetes Federation MetS criteria. Among the 600 participants (10.5%) with baseline AVC, neither MetS nor diabetes was associated with AVC progression.ConclusionsIn the MESA cohort, MetS was associated with a significant increase in incident ("new") AVC, raising the possibility that MetS may be a potential therapeutic target to prevent AVC development

Sylviculture et nutrition des accrus de frêne dans les Hautes-Pyrénées

Le projet CHAPAY a contribué à produire des connaissances, des méthodes et des outils pour prendre en compte les relations entre le changement des activités agricoles et des paysages dans l’action publique et la gouvernance des territoires. Le frêne trouve dans de nombreux sites des Hautes-Pyrénées des conditions favorables à son installation, mais sa croissance est très variable selon les stations. L’exploitation forestière de ces accrus nécessite, au préalable, une connaissance du potentiel de croissance auquel on peut s’attendre selon la fertilité de la station concernée. Nos résultats sont fondés sur une étude de terrain portant sur des accrus représentatifs des Hautes-Pyrénées. Nous les avons classés en niveaux de potentiel de croissance actuels et futurs et nous avons interprété ces niveaux par rapport aux données de fertilité chimique des stations. Cette méthodologie peut être étendue à d’autres régions et à d’autres types d’accrus. Elle peut servir de base à une catégorisation des accrus selon leur intérêt écologique ou économique