No Effects of Acute Psychosocial Stress on Working Memory in Older People With Type 2 Diabetes

Type 2 diabetes (T2D) has been considered a public health threat due to its growing prevalence, particularly in the older population. It is important to know the effects of psychosocial stress and its potential consequences for some basic cognitive processes that are important in daily life. Currently, there is very little information about how people with T2D face acute psychosocial stressors, and even less about how their response affects working memory (WM), which is essential for their functionality and independence. Our aim was to characterize the response to an acute laboratory psychosocial stressor and its effects on WM in older people with T2D. Fifty participants with T2D from 52 to 77 years old were randomly assigned to a stress (12 men and 12 women) or control (12 men and 14 women) condition. Mood and physiological (cortisol, C, and salivary alpha-amylase, sAA) responses to tasks were measured. In addition, participants completed a WM test before and after the stress or control task. Our results showed that the TSST elicited higher negative affect and greater C and sAA responses than the control task. No significant differences in WM were observed depending on the exposure to stress or the control task. Finally, participants who showed higher C and sAA responses to the stressor had lower WM performance. Our results indicate that medically treated older adults with T2D show clear, typical mood and physiological responses to an acute psychosocial stressor. Finally, the lack of acute psychosocial stress effects on WM suggests that it could be related to aging and not to this disease, at least when T2D is adequately treated.

Copper(ii) complexes of macrocyclic and open-chain pseudopeptidic ligands: synthesis, characterization and interaction with dicarboxylates

This journal is © The Royal Society of Chemistry. Mono- and dinuclear Cu(ii) complexes were prepared with pseudopeptidic open chain and macrocyclic ligands, respectively. They were characterized by UV-vis spectroscopy, EPR, HRMS and X-ray diffraction. The Cu(ii) cation is coordinated by two amines and two deprotonated amides, in a slightly distorted square planar coordination geometry. The complexes interact with several substituted dicarboxylates, as shown by UV-vis titrations and EPR experiments. The interaction of both mono- and dinuclear complexes with very similar dicarboxylates of biological interest (malate and aspartate) resulted in strikingly different outcomes: in the first case a ternary complex [ligand⋯metal⋯dicarboxylate] was obtained almost quantitatively, while in the latter, the Cu(ii) displacement to form Cu(Asp)2 was predominant

Supplementary Material for: Reducing the Harmful Effects of Infrared Radiation on the Skin Using Bicosomes Incorporating β-Carotene

<b><i>Aim:</i></b> In this work the effect of infrared (IR) radiation, at temperatures between 25 and 30°C, on the formation of free radicals (FRs) in the skin is studied. Additionally, the influence of IR radiation at high temperatures in the degradation of skin collagen is evaluated. In both experiments the protective effect against IR radiation of phospholipid nanostructures (bicosomes) incorporating β-carotene (Bcb) is also evaluated. <b><i>Methods:</i></b> The formation of FRs in skin under IR exposure was measured near physiological temperatures (25-30°C) using 5,5-dimethyl-1-pyrroline-N-oxide spin trap and electron paramagnetic resonance (EPR) spectroscopy. The study of the collagen structure was performed by small-angle X-ray scattering using synchrotron radiation. <b><i>Results:</i></b> EPR results showed an increase in the hydroxyl radical in the irradiated skin compared to the native skin. The skin collagen was degraded by IR exposure at high temperatures of approximately 65°C. The treatment with Bcb reduced the formation of FRs and kept the structure of collagen. <b><i>Conclusions:</i></b> The formation of FRs by IR radiation does not depend on the increase of skin temperature. The decrease of FRs and the preservation of collagen fibers in the skin treated with Bcb indicate the potential of this lipid system to protect skin under IR exposure