Diet, Metabolites, and “Western-Lifestyle” Inflammatory Diseases

One explanation for the increased incidence of allergies, asthma, and even some autoimmune diseases has been the hygiene hypothesis. However, recent studies also highlight an important role for diet and bacterial metabolites in controlling various immune pathways, including gut and immune homeostasis, regulatory T cell biology, and inflammation. Dietary-related metabolites engage “metabolite-sensing” G-protein-coupled receptors, such as GPR43, GPR41, GPR109A, GPR120, and GPR35. These receptors are expressed on immune cells and some gut epithelial cells and generally mediate a direct anti-inflammatory effect. Insufficient intake of “healthy foodstuffs” adversely affects the production of bacterial metabolites. These metabolites and those derived directly from food drive beneficial downstream effects on immune pathways. We propose that insufficient exposure to dietary and bacterial metabolites might underlie the development of inflammatory disorders in Western countries. This review highlights what is currently known about diet, metabolites, and their associated immune pathways in relation to the development of inflammatory disease

Obésité, facteurs socio-démographiques et indicateurs de santé chez les personnes âgées à Marseille

L’objectif de cette étude est triple : (1) déterminer si les facteurs socio-démographiques que sont l’âge, le niveau d’éducation et le statut marital ont le même impact sur l’obésité chez les femmes et chez les hommes, âgés de 60 ans et plus ; (2) évaluer les associations entre d’une part l’obésité et, d’autre part, l’auto-évaluation de la santé, les incapacités physiques et l’estime de soi ; (3) tester le rôle médiateur potentiel des maladies cardio-vasculaires et du diabète sur la relation entre obésité et auto-évaluation de la santé. Pour cela, 400 personnes âgées de 60 à 92 ans, vivant à Marseille, ont été interrogées. Ces rencontres individuelles comprenaient une prise de mesures anthropométriques et un entretien dirigé à l’aide d’un questionnaire (durée moyenne : 1h30). La prévalence de l’obésité dans notre échantillon de population est de 17 %, taux comparable à l’ensemble de la population française du même âge. Nos analyses ont permis de montrer que les corrélats de l’obésité sont fort différents entre les femmes et les hommes âgés. Chez les hommes, seul le statut marital est significativement associé à l’obésité alors que chez les femmes, l’âge, le niveau d’éducation, l’auto-évaluation de la santé et les incapacités physiques sont associés à l’obésité. Enfin, nous avons montré que la relation entre obésité et auto-évaluation de la santé (observée chez les femmes) est une association indirecte « médiée » par les maladies cardio-vasculaires.The purpose of this study is threefold: (1) to determine whether the socio-demographic factors of age, level of education and marital status have the same impact on obesity in women and in men aged 60 years and above; (2) to evaluate the associations between obesity on the one hand and self-rated health, physical incapacities and self-esteem on the other; (3) to test the mediatory potential of cardio-vascular diseases and diabetes on the relationship between obesity and self-rated health. For this, 400 persons aged from 60 to 92 years, living in Marseille, were questioned. These individual encounters included anthropometric measurement, and an interview carried out with the aid of a questionnaire (average duration: 1h30). The prevalence of obesity in our population sample is 17%, a rate comparable to the whole of this age group in the French population. Our analyses show that the correlates of obesity are very different between older women and men. For the men, only marital status is significantly associated with obesity while for the women, age, education level, self-rated health and physical incapacities are associated with obesity. Finally we have shown that the relation between obesity and self-rated health (for the women) is an indirect association affected by cardio-vascular diseases

Relations entre l’estime de soi et l’état de santé « objectif » des aînés

Malgré de nombreuses études portant sur l’évolution de l’estime de soi au cours de la vie, les relations entre estime de soi, vieillissement et santé restent en partie inexplorées, particulièrement dans la population française. L’objectif de cette étude est double : (1) évaluer les relations entre l’estime de soi et les variables sociodémographiques chez les aînés, notamment l’âge et (2) si, comme nous le supposons, l’avancée en âge est associée à une baisse d’estime de soi : tester le rôle de médiateur des maladies chroniques et des incapacités physiques sur la relation entre estime de soi et avancée en âge. Pour cela, 400 personnes âgées de 60 à 92 ans, aux états de santé fort différents, ont été interviewées individuellement à Marseille (durée moyenne : 1 h 30). Dans cet échantillon, l’âge, le lieu de résidence et la catégorie socioprofessionnelle sont associés à l’estime de soi. Si les maladies chroniques n’ont pas d’effet sur l’estime de soi, les incapacités physiques y sont fortement associées. Nos analyses ont permis de montrer que la relation entre estime de soi négative et avancée en âge n’est pas directe, mais « médiée » par les incapacités physiques. Par ailleurs, et sans cette fois dichotomiser l’estime de soi, une analyse en pistes causales nous a permis de montrer que les incapacités physiques et l’institutionnalisation jouent des rôles de médiateurs entre l’âge et l’estime de soi, considérée cette fois comme variable continue. Ces résultats sont discutés par le biais des activités sociales, mais également à travers les relations de pouvoir inhérentes à la survenue de la dépendance.In spite of several studies on self-esteem covering the human life-span, the relation between self-esteem, aging and health remains incompletely explored, particularly in the French population. The objective of this study is twofold: (1) to assess the relation between self-esteem and socio-demographic factors, notably age, among older French adults, and (2) if, as is presumed, advancing age is associated with lower self-esteem, to test the mediating effect of chronic diseases and physical incapacities on the relation between age and negative self-esteem. For this, 400 older adults living in Marseille, aged from 60 to 92, were individually interviewed (average duration: 1 h 30). In this sample, age, place of residence and educational level were associated with self-esteem. Physical incapacities were also associated with self-esteem, but chronic diseases were not. Our analyses showed that the relationship between advancing age and negative self-esteem is not direct, but mediated by physical incapacities. On the other hand, and without dichotomizing self-esteem, analysis of cause indicates that the relation between age and self-esteem (entered in the model as a continuous variable) was mediated by physical incapacities and institutionalization. These results are discussed through the social activities theory, and through power relationships inherent in dependency

Relations entre l’estime de soi et l’état de santé « objectif » des aînés

Malgré de nombreuses études portant sur l’évolution de l’estime de soi au cours de la vie, les relations entre estime de soi, vieillissement et santé restent en partie inexplorées, particulièrement dans la population française. L’objectif de cette étude est double : (1) évaluer les relations entre l’estime de soi et les variables sociodémographiques chez les aînés, notamment l’âge et (2) si, comme nous le supposons, l’avancée en âge est associée à une baisse d’estime de soi : tester le rôle de médiateur des maladies chroniques et des incapacités physiques sur la relation entre estime de soi et avancée en âge. Pour cela, 400 personnes âgées de 60 à 92 ans, aux états de santé fort différents, ont été interviewées individuellement à Marseille (durée moyenne : 1 h 30). Dans cet échantillon, l’âge, le lieu de résidence et la catégorie socioprofessionnelle sont associés à l’estime de soi. Si les maladies chroniques n’ont pas d’effet sur l’estime de soi, les incapacités physiques y sont fortement associées. Nos analyses ont permis de montrer que la relation entre estime de soi négative et avancée en âge n’est pas directe, mais « médiée » par les incapacités physiques. Par ailleurs, et sans cette fois dichotomiser l’estime de soi, une analyse en pistes causales nous a permis de montrer que les incapacités physiques et l’institutionnalisation jouent des rôles de médiateurs entre l’âge et l’estime de soi, considérée cette fois comme variable continue. Ces résultats sont discutés par le biais des activités sociales, mais également à travers les relations de pouvoir inhérentes à la survenue de la dépendance.In spite of several studies on self-esteem covering the human life-span, the relation between self-esteem, aging and health remains incompletely explored, particularly in the French population. The objective of this study is twofold: (1) to assess the relation between self-esteem and socio-demographic factors, notably age, among older French adults, and (2) if, as is presumed, advancing age is associated with lower self-esteem, to test the mediating effect of chronic diseases and physical incapacities on the relation between age and negative self-esteem. For this, 400 older adults living in Marseille, aged from 60 to 92, were individually interviewed (average duration: 1 h 30). In this sample, age, place of residence and educational level were associated with self-esteem. Physical incapacities were also associated with self-esteem, but chronic diseases were not. Our analyses showed that the relationship between advancing age and negative self-esteem is not direct, but mediated by physical incapacities. On the other hand, and without dichotomizing self-esteem, analysis of cause indicates that the relation between age and self-esteem (entered in the model as a continuous variable) was mediated by physical incapacities and institutionalization. These results are discussed through the social activities theory, and through power relationships inherent in dependency

Periodic features in the Dynamic Structure Factor of the Quasiperiodic Period-doubling Lattice

We present an exact real-space renormalization group (RSRG) method for evaluating the dynamic structure factor of an infinite one-dimensional quasiperiodic period-doubling (PD) lattice. We observe that for every normal mode frequency of the chain, the dynamic structure factor $S(q,\omega)$ always exhibits periodicity with respect to the wave vector $q$ and the presence of such periodicity even in absence of translational invariance in the system is quite surprising. Our analysis shows that this periodicity in $S(q,\omega)$ actually indicates the presence of delocalized phonon modes in the PD chain. The Brillouin Zones of the lattice are found to have a hierarchical structure and the dispersion relation gives both the acoustic as well as optical branches. The phonon dispersion curves have a nested structure and we have shown that it is actually the superposition of the dispersion curves of an infinite set of periodic lattices.Comment: 9 pages, 3 postscript figures, REVTeX, To appear in Phys. Rev. B (1 February 1998-I

Archimedean-like colloidal tilings on substrates with decagonal and tetradecagonal symmetry

Two-dimensional colloidal suspensions subject to laser interference patterns with decagonal symmetry can form an Archimedean-like tiling phase where rows of squares and triangles order aperiodically along one direction [J. Mikhael et al., Nature 454, 501 (2008)]. In experiments as well as in Monte-Carlo and Brownian dynamics simulations, we identify a similar phase when the laser field possesses tetradecagonal symmetry. We characterize the structure of both Archimedean-like tilings in detail and point out how the tilings differ from each other. Furthermore, we also estimate specific particle densities where the Archimedean-like tiling phases occur. Finally, using Brownian dynamics simulations we demonstrate how phasonic distortions of the decagonal laser field influence the Archimedean-like tiling. In particular, the domain size of the tiling can be enlarged by phasonic drifts and constant gradients in the phasonic displacement. We demonstrate that the latter occurs when the interfering laser beams are not adjusted properly

Magnetic Quantum Tunneling: Insights from Simple Molecule-Based Magnets

This article takes a broad view of the understanding of magnetic bistability and magnetic quantum tunneling in single-molecule magnets (SMMs), focusing on three families of relatively simple, low-nuclearity transition metal clusters: spin S = 4 Ni4, Mn(III)3 (S = 2 and 6) and Mn(III)6 (S = 4 and 12). The Mn(III) complexes are related by the fact that they contain triangular Mn3 units in which the exchange may be switched from antiferromagnetic to ferromagnetic without significantly altering the coordination around the Mn(III) centers, thereby leaving the single-ion physics more-or-less unaltered. This allows for a detailed and systematic study of the way in which the individual-ion anisotropies project onto the molecular spin ground state in otherwise identical low- and high-spin molecules, thus providing unique insights into the key factors that control the quantum dynamics of SMMs, namely: (i) the height of the kinetic barrier to magnetization relaxation; and (ii) the transverse interactions that cause tunneling through this barrier. Numerical calculations are supported by an unprecedented experimental data set (17 different compounds), including very detailed spectroscopic information obtained from high-frequency electron paramagnetic resonance and low-temperature hysteresis measurements. Diagonalization of the multi-spin Hamiltonian matrix is necessary in order to fully capture the interplay between exchange and local anisotropy, and the resultant spin-state mixing which ultimately gives rise to the tunneling matrix elements in the high symmetry SMMs (ferromagnetic Mn3 and Ni4). The simplicity (low-nuclearity, high-symmetry, weak disorder, etc..) of the molecules highlighted in this study proves to be of crucial importance.Comment: 32 pages, incl. 6 figure

Biocultural determinants of overweight and obesity in the context of nutrition transition in Senegal: a holistic anthropological approach

Senegal is experiencing a rising obesity epidemic, due to the nutrition transition occurring in most African countries, and driven by sedentary behaviour and high-calorie dietary intake. In addition, the anthropological local drivers of the social valorization of processed high-calorie food and large body sizes could expose the population to obesity risk. This study aimed to determine the impact of these biocultural factors on the nutritional status of Senegalese adults. A mixed methods approach was used, including qualitative and quantitative studies. Between 2011 and 2013, fourteen focus group discussions (n=84) and a cross-sectional quantitative survey (n=313 women; n=284 men) of adults in three different socio-ecological areas of Senegal (rural: n=204; suburban: n=206; urban: n=187) were conducted. Dietary intake (Dietary Diversity Scores), physical activity (International Physical Activity Questionnaire), body weight norms (Body Size Scale), weight and health statuses (anthropometric measures and blood pressure) were measured. Middle-aged and older Senegalese women were found to value overweight/obesity more than younger Senegalese in all regions. In addition, young urban/suburban adults had a tendency for daily snacking whilst urban/suburban adults tended to be less physically active and had higher anthropometric means. A binary logistic regression model showed that being female, older, living in urban/suburban areas and valuing larger body size were independently associated with being overweight/obese, but not high-calorie diet. Univariate analyses showed that lower physical activity and higher socioeconomic status were associated with being overweight/obese. Finally, overweight/obesity, which is low in men, is associated with hypertension in the total sample. The nutrition transition is currently underway in Senegal's urban/suburban areas, with older women being more affected. Since several specific biocultural factors jointly contribute to this phenomenon, the study's findings suggest the need for local public health interventions that target women and which account for the anthropological specificities of the Senegalese population

Novel hybrid organic/inorganic 2D quasiperiodic PC: from diffraction pattern to vertical light extraction

Recently, important efforts have been dedicated to the realization of a fascinating class of new photonic materials or metamaterials, known as photonic quasicrystals (PQCs), in which the lack of the translational symmetry is compensated by rotational symmetries not achievable by the conventional periodic crystals. As ever, more advanced functionality is demanded and one strategy is the introduction of non-linear and/or active functionality in photonic materials. In this view, core/shell nanorods (NRs) are a promising active material for light-emitting applications. In this article a two-dimensional (2D) hybrid a 2D octagonal PQC which consists of air rods in an organic/inorganic nanocomposite is proposed and experimentally demonstrated. The nanocomposite was prepared by incorporating CdSe/CdS core/shell NRs into a polymer matrix. The PQC was realized by electron beam lithography (EBL) technique. Scanning electron microscopy, far field diffraction and spectra measurements are used to characterize the experimental structure. The vertical extraction of the light, by the coupling of the modes guided by the PQC slab to the free radiation via Bragg scattering, consists of a narrow red emissions band at 690 nm with a full width at half-maximum (FWHM) of 21.5 nm. The original characteristics of hybrid materials based on polymers and colloidal NRs, able to combine the unique optical properties of the inorganic moiety with the processability of the host matrix, are extremely appealing in view of their technological impact on the development of new high performing optical devices such as organic light-emitting diodes, ultra-low threshold lasers, and non-linear devices