78 research outputs found

    Greater socioenvironmental risk factors and higher chronic pain stage are associated with thinner bilateral temporal lobes

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    INTRODUCTION: Previous research indicates ethnic/race group differences in pain and neurodegenerative diseases. Accounting for socioenvironmental factors reduces ethnic/race group differences in clinical and experimental pain. In the current study sample, we previously reported that in individuals with knee pain, ethnic/race group differences were observed in bilateral temporal lobe thickness, areas of the brain associated with risk for Alzheimer\u27s disease, and related dementias. The purpose of the study was to determine if socioenvironmental factors reduce or account for previously observed ethnic/race group differences and explore if a combined effect of socioenvironmental risk and chronic pain severity on temporal lobe cortices is evident. METHODS: Consistent with the prior study, the sample was comprised of 147 adults (95 women, 52 men), 45-85 years of age, who self-identified as non-Hispanic Black (n = 72) and non-Hispanic White (n = 75), with knee pain with/at risk for osteoarthritis. Measures included demographics, health history, pain questionnaires, cognitive screening, body mass index, individual- and community-level socioenvironmental factors (education, income, household size, marital and insurance status, and area deprivation index), and brain imaging. We computed a summative socioenvironmental risk index. RESULTS: Regression analyses showed that with the inclusion of socioenvironmental factors, the model was significant (p \u3c .001), and sociodemographic (ethnic/race) group differences were not significant (p = .118). Additionally, findings revealed an additive stress load pattern indicating thinner temporal lobe cortices with greater socioenvironmental risk and chronic pain severity (p = .048). IMPLICATIONS: Although individual socioenvironmental factors were not independent predictors, when collectively combined in models, ethnic/race group differences in bilateral temporal lobe structures were not replicated. Further, combined socioenvironmental risk factors and higher chronic pain severity were associated with thinner bilateral temporal lobes

    Brain-predicted age difference mediates the association between PROMIS sleep impairment, and self-reported pain measure in persons with knee pain

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    Knee pain, the most common cause of musculoskeletal pain (MSK), constitutes a severe public health burden. Its neurobiological causes, however, remain poorly understood. Among many possible causes, it has been proposed that sleep problems could lead to an increase in chronic pain symptomatology, which may be driven by central nervous system changes. In fact, we previously found that brain cortical thickness mediated the relationship between sleep qualities and pain severity in older adults with MSK. We also demonstrated a significant difference in a machine-learning-derived brain-aging biomarker between participants with low-and high-impact knee pain. Considering this, we examined whether brain aging was associated with self-reported sleep and pain measures, and whether brain aging mediated the relationship between sleep problems and knee pain. Exploratory Spearman and Pearson partial correlations, controlling for age, sex, race and study site, showed a significant association of brain aging with sleep related impairment and self-reported pain measures. Moreover, mediation analysis showed that brain aging significantly mediated the effect of sleep related impairment on clinical pain and physical symptoms. Our findings extend our prior work demonstrating advanced brain aging among individuals with chronic pain and the mediating role of brain-aging on the association between sleep and pain severity. Future longitudinal studies are needed to further understand whether the brain can be a therapeutic target to reverse the possible effect of sleep problems on chronic pain

    Forty years of carabid beetle research in Europe - from taxonomy, biology, ecology and population studies to bioindication, habitat assessment and conservation

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    Volume: 100Start Page: 55End Page: 14

    Discrimination in the solid state during crystallization : application to phenanthrene ultrapurification

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    La cristallisation est un processus d’auto-assemblement de molĂ©cules Ă  partir d’une phase dĂ©sordonnĂ©e (liquide, amorphe ou gazeuse). De façon gĂ©nĂ©rale, la miscibilitĂ© Ă  l’état solide entre un constituant d’intĂ©rĂȘt et son impuretĂ© dĂ©pendent d’une part, de la structure molĂ©culaire de ces deux espĂšces, et d’autre part, de la structure cristalline du rĂ©seau hĂŽte, c’est-Ă -dire celui du composĂ© d’intĂ©rĂȘt. En cas d’absence de miscibilitĂ©, l’optimisation des conditions de cristallisation permet un retrait total de l’impuretĂ© du composĂ© visĂ©. Cette thĂšse vise Ă  dĂ©montrer que, lorsque deux molĂ©cules sont semblables et que leur structure cristalline est peu dense, des solutions solides de substitutions peuvent se former et empĂȘcher le retrait de l’impuretĂ© de l’espĂšce cible. Inversement, lorsque les impuretĂ©s sont trĂšs difĂ©rentes de l’espĂšce Ă  purifer, l’absence de solution solide est observĂ©e et permet leur Ă©limination totale grĂące Ă  une bonne discrimination Ă  l’état solide. Le systĂšme du phĂ©nanthrĂšne, un composĂ© servant entre autres de base pour la synthĂšse de composĂ©smorphiniques, a Ă©tĂ© choisi pour illustrer cette thĂšse. Diverses mĂ©thodes de cristallisation (fusion de zone, co-cristallisation, recristallisation en solution, sublimation-condensation) ont Ă©tĂ© testĂ©es et ont permis, aprĂšs optimisation et combinaison, l’obtention Ă  l’échelle prĂ©parative de phĂ©nanthrĂšne pur Ă  plus de 99,999 % en moles, ce qui le place sur l’échelle de l’ultra-puretĂ© (puretĂ© > 99,9 % en moles).Crystallization is a process during which molecules self assembly from a disordered (liquid, amorphous or gaseous) phase. The miscibility in the solid state between a component of interest and its impurity depends on: (i) their molecular structures, (ii) the crystal structure of the host lattice (namely, that of the component of interest). When no solid solution exists, the impurity can be completely eliminated from the target product after optimization of the crystallization conditions.The present thesis intends to demonstrate that, when two compounds present similar molecular structures with low-density crystal structures, solid solution formation can occur which prevents from their complete separation. Conversely, in case of sufcient dissimilarity, no solid solution is stable and their separation is possible thanks to a large discrimination in the solid state. The phenanthrene system – a model compound used as base for the synthesis of morphine derivatives – was chosen to illustrate this thesis. Several crystallization methods (zone melting, co-crystallization, solvent assisted crystallization and sublimation-condensation) were investigated and permitted, after optimization and combination, to obtain 99.999(9) mole % purity phenanthrene (which is above the ultrapure grade of 99.9 mole %)

    Discrimination à l'état solide durant la cristallisation : application à l'ultrapurification du phénanthréne

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    Crystallization is a process during which molecules self assembly from a disordered (liquid, amorphous or gaseous) phase. The miscibility in the solid state between a component of interest and its impurity depends on: (i) their molecular structures, (ii) the crystal structure of the host lattice (namely, that of the component of interest). When no solid solution exists, the impurity can be completely eliminated from the target product after optimization of the crystallization conditions.The present thesis intends to demonstrate that, when two compounds present similar molecular structures with low-density crystal structures, solid solution formation can occur which prevents from their complete separation. Conversely, in case of sufcient dissimilarity, no solid solution is stable and their separation is possible thanks to a large discrimination in the solid state. The phenanthrene system – a model compound used as base for the synthesis of morphine derivatives – was chosen to illustrate this thesis. Several crystallization methods (zone melting, co-crystallization, solvent assisted crystallization and sublimation-condensation) were investigated and permitted, after optimization and combination, to obtain 99.999(9) mole % purity phenanthrene (which is above the ultrapure grade of 99.9 mole %).La cristallisation est un processus d’auto-assemblement de molĂ©cules Ă  partir d’une phase dĂ©sordonnĂ©e (liquide, amorphe ou gazeuse). De façon gĂ©nĂ©rale, la miscibilitĂ© Ă  l’état solide entre un constituant d’intĂ©rĂȘt et son impuretĂ© dĂ©pendent d’une part, de la structure molĂ©culaire de ces deux espĂšces, et d’autre part, de la structure cristalline du rĂ©seau hĂŽte, c’est-Ă -dire celui du composĂ© d’intĂ©rĂȘt. En cas d’absence de miscibilitĂ©, l’optimisation des conditions de cristallisation permet un retrait total de l’impuretĂ© du composĂ© visĂ©. Cette thĂšse vise Ă  dĂ©montrer que, lorsque deux molĂ©cules sont semblables et que leur structure cristalline est peu dense, des solutions solides de substitutions peuvent se former et empĂȘcher le retrait de l’impuretĂ© de l’espĂšce cible. Inversement, lorsque les impuretĂ©s sont trĂšs difĂ©rentes de l’espĂšce Ă  purifer, l’absence de solution solide est observĂ©e et permet leur Ă©limination totale grĂące Ă  une bonne discrimination Ă  l’état solide. Le systĂšme du phĂ©nanthrĂšne, un composĂ© servant entre autres de base pour la synthĂšse de composĂ©smorphiniques, a Ă©tĂ© choisi pour illustrer cette thĂšse. Diverses mĂ©thodes de cristallisation (fusion de zone, co-cristallisation, recristallisation en solution, sublimation-condensation) ont Ă©tĂ© testĂ©es et ont permis, aprĂšs optimisation et combinaison, l’obtention Ă  l’échelle prĂ©parative de phĂ©nanthrĂšne pur Ă  plus de 99,999 % en moles, ce qui le place sur l’échelle de l’ultra-puretĂ© (puretĂ© > 99,9 % en moles)
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