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Increasing evidence suggests an association between typical age-related changes in sleep and brain structure. Here we review studies exploring the association between human histo-pathological and in vivo neuroimaging markers of brain structure and sleep-wake parameters in healthy older adults. Evidence from both large-scale epidemiological studies and in-lab quantification of specific sleep signatures are reviewed and advantages and pitfalls highlighted. Overall, the results point to an association between sleep-wake disruption and both local and diffuse changes in brain structure. The associative strength largely varies between studies and seems to partially depend on the sleep trait under investigation. The role of specific sleep-wake regulating mechanisms on human cognitive and brain fitness and more particularly their causal relationship remains to be disentangled.

Community and abundance patterns of meiofauna and Harpacticoida in the Kuril-Kamchatka Trench, that trench’s slope and adjacent abyssal plain which is located in the North-Western Pacific were investigated in relation to environmental variables. Overall, Nematoda was the dominant taxon of the meiofauna community (93%), followed by Copepoda (3%). Nineteen harpacticoid families and 1 subfamily were found, whereby the family Ameiridae was most abundant in the study area. Within eight selected (sub)families (Argestidae, Aegisthidae, Ancorabolidae, Canthocamptidae, Cletodidae, Cylindropsyllinae, Parameiropsidae, Zosimeidae) 27 genera were found, with Zosime and Mesocletodes being most abundant. Dispersion effects characterized the meiofauna community abundances, while the Harpacticoida communities in the hadal and abyssal were distinct. The main contributor to the dissimilarities observed were Nematoda, Ameiridae, Zosime and Mesocletodes. Food availability, sediment composition and water depth are environmental drivers structuring the investigated communities in the abyssal and hadal. For the trench slope, no correlations with the investigated environmental variables were found. Very likely variables other than the investigated ones act as environmental drivers for the trench slope (e.g. topography). Furthermore, a tendency of meiofauna to increase in total abundances was detected with increasing depth in the deeper stations starting at 6000 m. In contrast, total Harpacticoida abundances decrease with depth. Considering the abundance of Harpacticoida families and genera individually, the abundance of some taxa decreased in the trench slope but increased in the trench floor (Zosimeidae, Miraciidae, Argestidae, Parameiropsis, Zosime). Diversity indices based on Harpacticoida genus and family level were not distinguishable with the exception of equitability (J) at the genus level (abyssal vs hadal; trench slope vs hadal).

Italy and Belgium have been among the first western countries to face the Coronavirus disease 2019 (COVID-19) emergency, imposing a total lockdown over the entire national territories. These limitations have proven effective in slowing down the spread of the infection. However, the benefits obtained in public health have come with huge costs in terms of social, economic, and psychological well-being. In the current study, we aimed to investigate how the period of home confinement affected self-reported sleep characteristics in Italians and Belgians, with special regard to sleep timing and subjective quality. Using an online survey we collected data from 2272 participants, 1622 Italians (Mage = 34.1 ± 13.6 years, 1171 F), and 650 Belgian (Mage = 43.0 ± 16.8 years, 509 F). Participants reported their sleep pattern (eg, bedtime, risetime) and perceived sleep quality during and, retrospectively, before the lockdown. During the lockdown, sleep timing was significantly delayed, time spent in bed increased, and sleep quality was markedly impaired in both Italians and Belgians. The most vulnerable individuals appeared to be women, subjects experiencing a more negative mood, and those perceiving the pandemic situation as highly stressful. However, the two samples differed in the subgroups most affected by the changes, possibly because of the different welfare systems of the two countries. In fact, in the Italian sample sleep quality and timing underwent significant modifications especially in unemployed participants, whereas in the Belgian sample this category was the one who suffered less from the restrictions. Considering that the novel coronavirus has spread across the whole globe, involving countries with different types of health and welfare systems, understanding which policy measures have the most effective protective role on physical and mental health is of primary importance.

This work is focused on applying structural concepts and basic chemical principles to model two N-heterocyclic lithium salts, based on trifluoromethyl substituted pyrazolide anions. An easily upscalable preparation method without difficult purification steps was also developed. In a comparative study, the physicochemical properties of the two new lithium salts were investigated, particularly the effect of an additional BF3-group at the nitrogen atom. In comparison to non-substituted lithium pyrazolide, the BF3-addition led to a strong improvement of thermal and electrochemical stability, ionic conductivity, as well as better C-rate and cycling performance. Furthermore, the anodic stability of Al current collectors was investigated and compared to commercial lithium salts, namely LiPF6 and lithium bis((trifluoromethyl)sulfonyl)imide (LiTFSI). Possible mechanisms that lead to the presented improvements are discussed.

Period3 (Per3) is one of the most robustly rhythmic genes in humans and animals. It plays a significant role in temporal organisation in peripheral tissues. The effects of PER3 variants on many phenotypes have been investigated in targeted and genome-wide studies. PER3 variants, especially the human variable number tandem repeat (VNTR), associate with diurnal preference, mental disorders, non-visual responses to light, brain and cognitive responses to sleep loss/circadian misalignment. Introducing the VNTR into mice alters responses to sleep loss and expression of sleep homeostasis-related genes. Several studies were limited in size and some findings were not replicated. Nevertheless, the data indicate a significant contribution of PER3 to sleep and circadian phenotypes and diseases, which may be connected by common pathways. Thus, PER3-dependent altered light sensitivity could relate to high retinal PER3 expression and may contribute to altered brain response to light, diurnal preference and seasonal mood. Altered cognitive responses during sleep loss/circadian misalignment and changes to slow wave sleep may relate to changes in wake/activity-dependent patterns of hypothalamic gene expression involved in sleep homeostasis and neural network plasticity. Comprehensive characterisation of effects of clock gene variants may provide new insights into the role of circadian processes in health and disease.

Lack of sleep has a considerable impact on vigilance: we perform worse, we make more errors, particularly at night, when we should be sleeping. Measures of brain functional connectivity suggest that decrease in vigilance during sleep loss is associated with an impaired cross-talk within the fronto-parietal cortex. However, fronto-parietal effective connectivity, which is more closely related to the causal cross-talk between brain regions, remains unexplored during prolonged wakefulness. In addition, no study has simultaneously investigated brain effective connectivity and wake-related changes in vigilance, preventing the concurrent incorporation of the two aspects. Here, we used electroencephalography (EEG) to record responses evoked by Transcranial Magnetic Stimulation (TMS) applied over the frontal lobe in 23 healthy young men (18-30 yr.), while they simultaneously performed a vigilance task, during 8 sessions spread over 29 h of sustained wakefulness. We assessed Response Scattering (ReSc), an estimate of effective connectivity, as the propagation of TMS-evoked EEG responses over the fronto-parietal cortex. Results disclose a significant change in fronto-parietal ReSc with time spent awake. When focusing on the night-time period, when one should be sleeping, participants with lower fronto-parietal ReSc performed worse on the vigilance task. Conversely, no association was detected during the well-rested, daytime period. Night-time fronto-parietal ReSc also correlated with objective EEG measures of sleepiness and alertness. These changes were not accompanied by variations in fronto-parietal response complexity. These results suggest that decreased brain response propagation within the fronto-parietal cortex is associated to increased vigilance failure during night-time prolonged wakefulness. This study reveals a novel facet of the detrimental effect on brain function of extended night-time waking hours, which is increasingly common in our societies.

Background Routine screening for perinatal depression is not common in most primary health care settings. The U.S. Preventive Services Task Force only recently updated their recommendation on depression screening to specifically recommend screening during the pre- and postpartum periods. While practitioners in high-income countries can respond to this new recommendation by implementing one of several existing depression screening tools developed in Western contexts, such as the Edinburgh Postnatal Depression Scale (EPDS) or the Patient Health Questionnaire-9 (PHQ-9), these tools lack strong evidence of cross-cultural equivalence, validity for case finding, and precision in measuring response to treatment in developing countries. Thus, there is a critical need to develop and validate new screening tools for perinatal depression that can be used by lay health workers, primary health care personnel, and patients. Methods Working in rural Kenya, we used free listing, card sorting, and item analysis methods to develop a locally-relevant screening tool that blended Western psychiatric concepts with local idioms of distress. We conducted a validation study with a random sample of 193 pregnant women and new mothers to test the diagnostic accuracy of this scale along with the EPDS and PHQ-9. Results The sensitivity/specificity of the EPDS and PHQ-9 was estimated to be 0.70/0.72 and 0.70/0.73, respectively. This compared to sensitivity/specificity of 0.90/0.90 for a new 9-item locally-developed tool called the Perinatal Depression Screening (PDEPS). Across these three tools, internal consistency reliability ranged from 0.77 to 0.81 and test-retest reliability ranged from 0.57 to 0.67. The prevalence of depression ranges from 5.2% to 6.2% depending on the clinical reference standard. Conclusion The EPDS and PHQ-9 are valid and reliable screening tools for perinatal depression in rural Western Kenya, the PDEPS may be a more useful alternative. At less than 10%, the prevalence of depression in this region appears to be lower than other published estimates for African and other low-income countries.

The aim of this study was the investigation of abundance, composition and biodiversity of benthic deep-sea Harpacticoida (Crustacea, Copepoda) in the Vema Fracture Zone (VFZ) and Puerto Rico trench. The study revealed a clear East-West gradient in total abundance of Harpacticoida with a westward decrease in abundances in the VFZ and significant differences in the community composition in the Eastern (East Vema) and Western Atlantic basin (West Vema) on family and genus level. The Puerto Rico trench and its upper slope did not only differ in abundance, but were distinct with respect to community composition on family and genus level. Thus, the upper slope might be considered as an ecotone, a transition zone where a rapid distinction of species composition occurs. In our study fiarea, 837 adult harpacticoid specimens could be assigned to 16 families and 1 subfamily. The most abundant families found were Ameiridae Boeck, 1865, Pseudotachidiidae Lang, 1936 and Ectinosomatidae Sars, 1903. Genera and species were investigated within selected families (Argestidae Por, 1986 , Cletodidae T. Scott, 1905 , Canthocamptidae Brady, 1880 and Zosimeidae Seifried, 2003) where 11 genera, and 73 species could be discriminated. Within the selected families, the genera Zosime Boeck, 1873 and Mesocletodes Sars, 1909 were dominant. In the study area, a high number of singletons was detected, which might be endemic to the respective region. Furthermore, a low total number of species in the trench was observed which was attributed to frequent disturbances in the dynamic environment of the Puerto Rico trench (e.g. turbidites or seismic activity) and high adaptability of specialists and opportunists to these disturbances.

We studied meiofauna standing stocks and community structure in the Kuril–Kamchatka Trench and its adjacent abyssal plains in the northwestern Pacific Ocean. In general, the Nematoda were dominant (93%) followed by the Copepoda (4%). Nematode abundances ranged from 87% to 96%; those of copepods from 2% to 7%. The most diverse deployment yielded 17 taxa: Acari, Amphipoda, Annelida, Bivalvia, Coelenterata, Copepoda, Cumacea, Gastrotricha, Isopoda, Kinorhyncha, Loricifera, Nematoda, Ostracoda, Priapulida, Tanaidacea, Tantulocarida, and Tardigrada. Nauplii were also present. Generally, the trench slope and the southernmost deployments had the highest abundances (850–1392 individuals/cm 2 ). The results of non-metric multidimensional scaling indicated that these deployments were similar to each other in meiofauna community structure. The southernmost deployments were located in a zone of higher particulate organic carbon (POC) flux (g C org m −2 yr −1 ), whereas the trench slope should have low POC flux due to depth attenuation. Also, POC and abundance were significantly correlated in the abyssal plains. This correlation may explain the higher abundances at the southernmost deployments. Lateral transport was also assumed to explain high meiofauna abundances on the trench slope. Abundances were generally higher than expected from model results. ANOSIM revealed significant differences between the trench slope and the northern abyssal plains, between the central abyssal plains and the trench slope, between the trench slope and the southern abyssal plains, between the central and the southern abyssal plains, and between the central and northern deployments. The northern and southern abyssal plains did not differ significantly. In addition, a U -test revealed highly significant differences between the trench-slope and abyssal deployments. The taxa inhabited mostly the upper 0–3 cm of the sediment layer (Nematoda 80–90%; Copepoda 88–100%). The trench-slope and abyssal did not differ in occupancy of the top layer. Furthermore, sediment depth and abundance were strongly correlated, but the sediment texture itself and the grain sizes showed only slight correlations with abundance. In the trench slope no correlation between sediment texture and abundance was found. We suggest that sediment is not the only factor that affects meiofauna abundance in the study area. The results of our study were compared with other trench and nontrench studies, and in most cases, the abundance decreases with depth initially but increases again below a certain depth, especially in deep-sea trenches below productive waters. No generalization can be made, however, about the depth at which the reversal occurs; it depends on the area of investigation and on a mixture of many other factors (e.g., sediment heterogeneity, oxygen, redox potential, proximity to land masses, and season).

Objectif La fragmentation du cycle veille-sommeil augmente avec l’âge. Ici, nous explorons la sieste comme indicateur de cette fragmentation et son impact sur les performances cognitives. Methodes Des donnees d’actimetrie ont ete collectees chez 35 personnes âgees (57–85 ans, 18 femmes, 19 siesteurs [sieste > 20 min/jour, > 3 fois/semaine, depuis > 1 an]). La fragmentation du sommeil a ete evaluee grâce a la probabilite de transition d’une periode de repos vers une periode d’activite (kRA). Pour la fragmentation d’eveil, la probabilite de transition d’une periode d’activite vers une periode de repos (kAR) et la fraction de sommeil au cours de l’apres-midi (fSoD) ont ete examinees. Un score composite de cognition globale et un score specifique des fonctions executives ont ete calcules. Resultats Une comparaison de groupes confirme que les siesteurs presentent une fragmentation de la periode d’eveil plus elevee que les non siesteurs (fSoD : p Conclusion La fraction de sommeil au cours de l’apres-midi mesuree par l’actimetrie peut etre utilisee comme une mesure quantitative de la sieste. Cette mesure de fragmentation d’eveil semble jouer un role dans le declin des performances cognitives au cours du vieillissement.

Short-term memory (STM) for order information, as compared to STM for item information, has been shown to be a critical determinant of language learning capacity. The present fMRI study asked whether the neural substrates of order STM can serve as markers for bilingual language achievement. Two groups of German-French bilinguals differing in second language proficiency were presented STM tasks probing serial order or item information. During order STM but not item STM tasks, the high proficiency group showed increased activation in the lateral orbito-frontal and the superior frontal gyri associated with updating and grouped rehearsal of serial order information. Functional connectivity analyses for order encoding showed a functional network involving the left IPS, the right IPS and the right superior cerebellum in the high proficiency group while the low proficiency group showed enhanced connectivity between the left IPS and bilateral superior temporal and temporo-parietal areas involved in item processing. The present data suggest that low proficiency bilinguals activate STM networks for order in a less efficient and differentiated way, and this may explain their poorer storage and learning capacity for verbal sequences.

Objectives The aim of this study was to determine the prevalence of dependence on prescription drugs (DPD) and associated comorbid disorders in consecutive general hospital inpatients. Methods The sample consisted of 952 volunteer patients (age range, 18 to 64 years) in a German general hospital. The screening instrument was a self-administered questionnaire. A personal interview containing the Structured Clinical Interview for DSM-IV (SCID, Axis I) was used to evaluate positive screening results and to diagnose comorbid disorders. Results The current prevalence of DPD was 4.7% [95% confidence interval (CI), 3.40–6.18; n=45). The current prevalence of single sedative dependence was 1.4% (95% CI, 0.62–2.14); of single hypnotic dependence, 1.2% (95% CI, 0.47–1.87); and of painkillers, 1.3% (95% CI, 0.54–2.01). In addition, dependence on sedatives and hypnotics was found in 0.1% of screened patients, painkillers and sedatives in 0.2%, painkillers and hypnotics in 0.4% and all three substances in 0.2%. Women were slightly overrepresented. The average age was 50.3 years. Psychiatric Axis I comorbidities were diagnosed in 66.7% of all cases, mostly anxiety disorders, followed by comorbid substance use and affective disorders. Conclusion The results indicate that the prevalence of DPD in general hospitals is frequent and should therefore become an important subject for health care providers. The general hospital might serve as an appropriate setting to provide early interventions for this group of patients.

Holter monitoring was performed in 202 patients with idiopathic dilated cardiomyopathy, which revealed accelerated idioventricular rhythm in 16 patients (8%) and nonsustained ventricular tachycardia in 70 patients (35%). During 32 +/- 15-month prospective follow-up, no significant difference was observed for major arrhythmic events and transplant-free survival between patients with and without accelerated idioventricular rhythm, whereas patients with nonsustained ventricular tachycardia had a significantly higher incidence of major arrhythmic events and a lower transplant-free survival rate.

Based on the homology of human and monkey amyloid precursor proteins and the derived β -amyloid peptides (A β ) the investigation of brains from old monkeys might be useful for the understanding of β -amyloidosis in the aetiology of Alzheimer's disease. In the present study, the prefrontal cortex, which is known to be highly susceptible to the deposition of A β , was screened for the occurrence of senile plaques in perfused tissue of aged rhesus monkeys ( Macaca mulatta ). A β deposits were immunocytochemically detected in five of six macaques aged about 28 years. Differently N-terminal truncated A β species in the senile plaques were simultaneously detected by a carbocyanine double fluorescence method applying the bright red fluorescent Cy3 and the novel green fluorescent Cy2. In a few cases, immunoreactivity for the shortened fragment containing the amino acids 17–42 (A β 17–42 ; p3 fragment with a molecular weight of 3 kDa) was demonstrated in deposits apparently devoid of A β 8–17 . Senile plaques were further characterized by carbocyanine double labelling of A β and astrocytes, microglia and apolipoprotein E.© 1997 Elsevier Science B.V. All rights reserved.

Objectif Dans cette etude nous examinons le role d’une exposition prolongee a la lumiere comme une contre-mesure aux effets deleteres d’une privation de sommeil sur la vigilance, les profils circadiens de la melatonine et du cortisol, et sur la variation de temperature et d’activite chez des sujets jeunes et âges. Methodes Vingt-six jeunes participants et 12 plus âges ont effectues 3 sessions au sein du laboratoire, qui consistaient en une privation de sommeil de 40 h avec une exposition prolongee a une lumiere faible (DL : 8 lux), a une lumiere blanche (WL : 250 lux) ou a une lumiere blanche enrichie en rayon bleus (BL : 250 lux). Des questionnaires et des tests cognitifs ont ete completes regulierement afin d’evaluer le degre de fatigue des participants et des echantillons salivaires ont ete collectes pour estimer le profil de la melatonine et du cortisol. La temperature de la peau ainsi que l’activite ont ete enregistrees en continue. Resultats L’exposition a la lumiere lors d’un eveil prolonge induit une diminution significative de la fatigue chez les jeunes et les plus âges. Au contraire, la diminution de la concentration de la melatonine est observee uniquement chez les jeunes que la lumiere soit enrichie en rayon bleu ou non. Aucune difference significative n’est observee pour le cortisol avec la WL comparee a la DL dans les 2 groupes, mais l’exposition a la BL diminue le niveau chez les jeunes alors qu’elle l’augmente chez les plus âges. Aucune difference significative n’a ete demontree dans les 2 groupes pour le test visuel du 3-back lorsque les participants sont exposes a la BL, cependant, l’exposition a la WL diminue les performances chez les jeunes. La temperature est augmentee uniquement chez les plus âges apres la BL et la WL. La BL augmente l’activite chez les jeunes alors qu’elle la diminue chez les plus âges, contrairement a la WL qui diminue l’activite chez les plus jeunes et l’augmente chez les plus âges. Conclusion Nos resultats demontrent la presence d’une modulation liee a l’âge des effets non visuels de la lumiere lors d’un eveil prolonge. Ainsi, l’utilisation d’une lumiere d’intensite moderee lors du travail de nuit a des effets differents sur les travailleurs jeunes et plus âges.