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Our study aimed to (1) identify trajectories on different mental health components during a two-year follow-up of the COVID-19 pandemic and contextualise them according to pandemic periods; (2) investigate the associations between mental health trajectories and several exposures, and determine whether there were differences among the different mental health outcomes regarding these associations.
Methods
We included 5535 healthy individuals, aged 40–65 years old, from the Barcelona Brain Health Initiative (BBHI). Growth mixture models (GMM) were fitted to classify individuals into different trajectories for three mental health-related outcomes (psychological distress, personal growth and loneliness). Moreover, we fitted a multinomial regression model for each outcome considering class membership as the independent variable to assess the association with the predictors.
Results
For the outcomes studied we identified three latent trajectories, differentiating two major trends, a large proportion of participants was classified into ‘resilient’ trajectories, and a smaller proportion into ‘chronic-worsening’ trajectories. For the former, we observed a lower susceptibility to the changes, whereas, for the latter, we noticed greater heterogeneity and susceptibility to different periods of the pandemic. From the multinomial regression models, we found global and cognitive health, and coping strategies as common protective factors among the studied mental health components. Nevertheless, some differences were found regarding the risk factors. Living alone was only significant for those classified into ‘chronic’ trajectories of loneliness, but not for the other outcomes. Similarly, secondary or higher education was only a risk factor for the ‘worsening’ trajectory of personal growth. Finally, smoking and sleeping problems were risk factors which were associated with the ‘chronic’ trajectory of psychological distress.
Conclusions
Our results support heterogeneity in reactions to the pandemic and the need to study different mental health-related components over a longer follow-up period, as each one evolves differently depending on the pandemic period. In addition, the understanding of modifiable protective and risk factors associated with these trajectories would allow the characterisation of these segments of the population to create targeted interventions.
The only available genome-wide study (Minelli et al., 2018) indicated an association between the neglect CT and MED22, a transcriptional factor gene.
Objectives
To verify how the dysregulation of MED22 could be affected by environmental and genetic factors, we carried out an analysis on these components and a longitudinal study concerning the effect of trauma-focused psychotherapy in MDD patients that experienced CT.
Methods
On a large mRNA sequencing dataset including 368 MDD patients we computed the genetic (GReX) and the environmental (EReX) components affecting gene expression in relation to CT. Furthermore, we measured the expression of MED22 in 22 MDD patients treated with trauma-focused psychotherapy.
Results
The dissection of MED22 expression profiles revealed an association of neglect with environmental and genetic components (p=6x10-3 p=2.6x10-4). Furthermore, in an independent cohort of 177 controls, we also observed a significant association between cis-eSNPs of MED22 and higher neuroticism scores (best p-value: 0.00848) that are usually associated with a decreased amount of resilience to stress events. Finally, the results of psychotherapy revealed a reduction of depressive symptomatology (p<0.001) and 73% of patients resulted responders at the follow-up visit. MED22 expression during psychotherapy showed a change trend (p=0.057) with an interaction effect with response (p=0.035). Responder and non-responder patients showed MED22 expression differences at different trauma-focused psychotherapy timepoints (p=0.15; p=0.012) and at the follow-up (p=0.021).
Conclusions
Our results provide insights suggesting that some biological and clinical consequences of CT depend on genetic background and environmental factors that could induce vulnerability or resilience to stressful life events.
This article is a clinical guide which discusses the “state-of-the-art” usage of the classic monoamine oxidase inhibitor (MAOI) antidepressants (phenelzine, tranylcypromine, and isocarboxazid) in modern psychiatric practice. The guide is for all clinicians, including those who may not be experienced MAOI prescribers. It discusses indications, drug-drug interactions, side-effect management, and the safety of various augmentation strategies. There is a clear and broad consensus (more than 70 international expert endorsers), based on 6 decades of experience, for the recommendations herein exposited. They are based on empirical evidence and expert opinion—this guide is presented as a new specialist-consensus standard. The guide provides practical clinical advice, and is the basis for the rational use of these drugs, particularly because it improves and updates knowledge, and corrects the various misconceptions that have hitherto been prominent in the literature, partly due to insufficient knowledge of pharmacology. The guide suggests that MAOIs should always be considered in cases of treatment-resistant depression (including those melancholic in nature), and prior to electroconvulsive therapy—while taking into account of patient preference. In selected cases, they may be considered earlier in the treatment algorithm than has previously been customary, and should not be regarded as drugs of last resort; they may prove decisively effective when many other treatments have failed. The guide clarifies key points on the concomitant use of incorrectly proscribed drugs such as methylphenidate and some tricyclic antidepressants. It also illustrates the straightforward “bridging” methods that may be used to transition simply and safely from other antidepressants to MAOIs.
The only available genome-wide study (Minelli et al., 2018) indicated an association between the neglect CT and MED22, a transcriptional factor gene. To verify how the dysregulation of MED22 could be affected by environmental and genetic factors, we carried out an analysis on these components and a longitudinal study concerning the effect of trauma-focused psychotherapy in MDD patients that experienced CT. On a large mRNA sequencing dataset including 368 MDD patients we computed the genetic (GReX) and the environmental (EReX) components affecting gene expression in relation to CT. Furthermore, we measured the expression of MED22 in 22 MDD patients treated with trauma-focused psychotherapy. The dissection of MED22 expression profiles revealed an association of neglect with environmental and genetic components (p=6x10-3 p=2.6x10-4). Furthermore, in an independent cohort of 177 controls, we also observed a significant association between cis-eSNPs of MED22 and higher neuroticism scores (best p-value: 0.00848) that are usually associated with a decreased amount of resilience to stress events. Finally, the results of psychotherapy revealed a reduction of depressive symptomatology (p<0.001) and 73% of patients resulted responders at the follow-up visit. MED22 expression during psychotherapy showed a change trend (p=0.057) with an interaction effect with response (p=0.035). Responder and non-responder patients showed MED22 expression differences at different trauma-focused psychotherapy timepoints (p=0.15; p=0.012) and at the follow-up (p=0.021). Our results provide insights suggesting that some biological and clinical consequences of CT depend on genetic background and environmental factors that could induce vulnerability or resilience to stressful life events.
The relevance of the episodic memory in the prediction of brain aging is well known. The Face Name Associative Memory Exam (FNAME) is a valued associative memory measure related to Alzheimer’s disease (AD) biomarkers, such as amyloid-β deposition preclinical AD individuals. Previous validation of the Spanish version of the FNAME test (S-FNAME) provided normative data and psychometric characteristics. The study was limited to subjects attending a memory clinic and included a reduced sample with gender inequality distribution. The purpose of this study was to assess S-FNAME psychometric properties and provide normative data in a larger independent sample of cognitively healthy individuals.
Method:
S-FNAME was administered to 511 cognitively healthy volunteers (242 women, aged 41–65 years) participating in the Barcelona Brain Health Initiative cohort study.
Results:
Factor analysis supported construct validity revealing two underlying components: face-name and face-occupation and explaining 95.34% of the total variance, with satisfactory goodness of fit. Correlations between S-FNAME and Rey Auditory-Verbal Learning Test were statistically significant and confirmed its convergent validity. We also found weak correlations with non-memory tests supporting divergent validity. Women showed better scores, and S-FNAME was positively correlated with education and negatively with age. Finally, we generated normative data.
Conclusions:
The S-FNAME test exhibits good psychometric properties, consistent with previous findings, resulting in a valid and reliable tool to assess episodic memory in cognitively healthy middle-aged adults. It is a promising test for the early detection of subtle memory dysfunction associated with abnormal brain aging.
As in previous periods of quarantine, lockdown confinement measures dictated to control SARS-CoV-2 would be expected to negatively affect mental health. We investigated the immediate effects (over a 10 day period) of a strict nationwide stay-at-home order imposed in Spain, one of the countries most affected by the COVID-19 pandemic. Focusing our analysis on the feelings of loneliness, we obtained our measures within a social context characterised by strong and continuous public and governmental support for increasing social bonds and cooperation in order to face the common public threat. Leveraging data from the Barcelona Brain Health Initiative, a prospective population-based study cohort, the short UCLA Loneliness Scale was administered to 1604 participants 2 years and 1 year before the stay-at-home lockdown and repeated, on average, 10 days after the official confinement order issued by the Spanish government. Ratings of loneliness remained stable during the 2 years before lockdown; however, they decreased significantly during the early stages of home confinement. This effect was particularly significant for the item ‘feeling excluded from others’ and was also observed among individuals who were confined alone. Overall, the results suggest that gestures and manifestations of appreciation by people for the labour and efforts of certain individuals, along with official campaigns designed to promote feelings of inclusion and belonging, may have beneficial effects on feelings of loneliness, a negative emotional state strongly regarded as a risk factor for impaired mental and general health status. Further assessments during the later stages of home confinement are now warranted.
Structure and diversity of sessile zoobenthic assemblages seem to be driven not only by chemical-physical constraints and biological interactions but also by substrate lithology and its surface features. Nevertheless, broadly distributed crustose epilithic corallines could mask the role of substrate on animal settling. To evaluate the direct influence of different rocky substrates, occurrence and coverage of several sessile species, growing on the dark (i.e. coralline-free) face of sublittoral limestone and granite boulders were compared in the Tavolara MPA (Mediterranean Sea). The analysis of photographic samples demonstrated significant differences in terms of species composition and coverage, according to lithology. Moreover, limestone boulders were widely bare, while the cover per cent was almost total on granite. The leading cause of observed patterns could be the different level of dissolution of the two types of rocks, due to their different mineral composition and textural characteristics. Limestone has previously been shown to have higher dissolution compared with granite, and consequently, a more unstable surface. Our results suggest that, in dark habitats, the absence of the crustose coralline layer allows more rock dissolution and consequent lower stability of the limestone compared with granite, which, in turn, reduces the zoobenthos colonization.
The relationship between nonlinear large-scale dynamo action and the generation and transport of magnetic helicity is investigated at moderate values of the magnetic Reynolds number ($Rm$). The model consists of a helically forced, sheared flow in a Cartesian domain. The boundary conditions are periodic in the horizontal and impenetrable for the vertical. The magnetic field is required to be vertical at the upper and lower boundaries. There are two consequences of this choice; one is that the magnetic helicity is not gauge invariant, the second is that fluxes of magnetic helicity are allowed in and out of the domain. We select the winding gauge, define all the contributions to the evolution of the helicity in this gauge and measure these contributions for various solutions of the dynamo equations. We vary $Rm$ and the shear strength, and find a rich landscape of dynamo solutions including travelling waves, pulsating waves and non-wave-like solutions. We find that, at the $Rm$ considered, the main contribution to the growth of magnetic helicity comes from processes throughout the volume of the fluid and that boundary terms respond by limiting the growth. We find that, in this magnetic Reynolds number regime, helicity conservation is not a strong constraint on large-scale dynamo action. We speculate on what may happen at higher $Rm$.
The etiology of bipolar disorder (BD) is still poorly understood and it has been proposed that altered expression of multiple mRNAs, affecting neurotransmission, in psychotic subjects may be due to epigenetic mechanisms (e.g., DNA methylation or histone modification).
Aims
The present collaborative study was aimed to investigate, in subjects with BD, dysregulation of DNA methylation, in the brain-derived neurotrophic factor (BDNF), previously associated with psychosis and linked to epigenetic changes at promoter regions, and in the nociceptin gene (N/OFQ), a new proposed target in psychiatric disorders.
Methods
DNA was isolated from blood of patients diagnosed with BD (either type I [n = 19] or II [n = 20]) according to DSM-IV criteria, and from healthy controls (n = 20) and, thereafter, bisulfite conversion was performed. Real-Time Methylation Specific PCR (MSP) was used for the quantification of the methylated promoters in all samples.
Results
A hypermethylation of BDNF promoter region was observed in BD II patients (but not in BD I) compared to controls (CONT: 19.0 ± 3.2%; BD I: 27.2 ± 4.0%; BD II: 36.3 ± 6.2% * P = 0.0167; ANOVA F = 3.464; P = 0.0384; Bonferroni’s post hoc test). No significant differences were found for DNA methylation of N/OFQ promoter.
Conclusions
Present preliminary findings suggest selective changes in DNA methylation of BDNF promoter in type II bipolar patients and highlight the importance of epigenetic factors in mediating the onset and/or susceptibility to BD, providing new insight into the mechanisms of gene expression.
it is well established that adversities and GRIN2B genetic variants (encoding NMDAR GluN2B subunit) are independently associated with behavioral and cognitive impairments in childhood. However, a high proportion of children exposed to risk have good, long-term outcomes.
Objectives
for the first time, we explored how environmental adversities and GRIN2B genetic variants influence children's cognitive abilities and behavioral problems.
Aims
we adopted a gene-by-environment interaction (GxE) approach, to identify children with an unfavorable developmental outcome with the potential of better informing the understanding of susceptibility to developmental disorders.
Methods
6 SNPs of GRIN2B were genotyped in 625 children aged 6-11 years from an Italian community-based sample. The interactive effect of GRIN2B variants with 4 measures of adversities (low socioeconomic status - SES, preterm delivery, maternal smoking, absence of breastfeeding) was investigated upon cognitive abilities (vocabulary, block design, forward/backward digit spans of Wechsler's Intelligence Scale, and Rey Figure test) and parents-rated behavioral problems (Child Behavior Checklist/6-18).
Results
rs5796555 x gestational age interaction (p= .00145) influenced cognition, with lower IQ memory among children in the ‘A/A genotype and ≤ 36 gestational age’ group, compared to all other groups. Rs2268119 x SES interaction (p= .00008) influenced behavior, with more attention problems among children in the ‘either A/T or T/T genotype and low SES’ group, compared to all other groups.
Conclusions
GRIN2B targets children with the worst outcome in memory and attention functioning among children exposed to environmental adversities. Identification of children with the highest risk may prompt cost-effective preventive/treatment strategies.
The etiology of bipolar disorder (BD) is poorly understood, involving genetic, epigenetic mechanisms and environmental contributions.
Aim:
Among the candidate genes associated with major psychoses, the present study investigated the degree of DNA methylation at brain-derived neurotrophic factor (BDNF) gene promoter in peripheral blood mononuclear cells (PBMCs) isolated from bipolar patients.
Methods:
DNA was isolated from the blood of 94 BD patients (49 BD I and 45 BD II) and 52 controls and converted with sodium bisulfite. Real Time Methylation Specific PCR was performed to quantify promoter methylation.
Results:
A significant BDNF gene expression down-regulation was observed in BD II 0.53 ± 0.11%; p < 0.05), but not in BD I (1.13 ± 0.19%) patients compared with controls (CONT: 1±0.2%). Consistently, an hypermethylation of the BDNF promoter region was specifically found in BD II patients (CONT: 24.0 ± 2.1%; BDI: 20.4 ± 1.7%; BDII: 33.3 ± 3.5%, p < 0.05). of note, higher levels of DNA methylation were observed in BD subjects on pharmacological treatment with mood stabilizers plus antidepressants (34.6 ± 4.2%, predominantly BD II) compared with those exclusively on mood stabilizing agents (21.7 ± 1.8%; p < 0.01, predominantly BD I). Moreover, among the different pharmacological therapies, lithium (20.1 ± 3.8%, p < 0.05) and valproate (23.6 ± 2.9%, p < 0.05) were associated with a significant reduction of DNA methylation compared to other drugs (35.6 ± 4.6%).
Conclusions:
Present findings suggest selective changes in DNA methylation of BDNF promoter in subjects with BD type II and highlight the importance of epigenetic factors in mediating the patophysiology an treatment response of BD.
Recent advances in dynamo theory have been made by examining the competition between small- and large-scale dynamos at high magnetic Reynolds number $\mathit{Rm}$. Small-scale dynamos rely on the presence of chaotic stretching whilst the generation of large-scale fields occurs in flows lacking reflectional symmetry via a systematic electromotive force (EMF). In this paper we discuss how the statistics of the EMF (at high $\mathit{Rm}$) depend on the properties of the multi-scale velocity that is generating it. In particular, we determine that different scales of flow have different contributions to the statistics of the EMF, with smaller scales contributing to the mean without increasing the variance. Moreover, we determine when scales in such a flow act independently in their contribution to the EMF. We further examine the role of large-scale shear in modifying the EMF. We conjecture that the distribution of the EMF, and not simply the mean, largely determines the dominant scale of the magnetic field generated by the flow.
It has been shown that it is possible to measure the turbulent diffusivity of a magnetic field by a method involving oscillatory sources. So far the method has only been tried in the special case of two-dimensional fields and flows. Here we extend the method to three dimensions and consider the case where the flow is thermally driven convection in a large-aspect-ratio domain. We demonstrate that if the diffusing field is horizontal the method is successful even if the underlying flow can sustain dynamo action. We show that the resulting turbulent diffusivity is comparable with, although not exactly the same as, that of a passive scalar. We were not able to measure unambiguously the diffusivity if the diffusing field is vertical, but argue that such a measurement is possible if enough resources are utilized on the problem.
We argue that a method developed by Ångström (Ann. Phys. Chem., vol. 114, 1861, pp. 513–530) to measure the thermal conductivity of solids can be adapted to determine the effective diffusivity of a large-scale magnetic field in a turbulent electrically conducting fluid. The method consists of applying an oscillatory source and measuring the steady-state response. We illustrate this method in a two-dimensional system. This geometry is chosen because it is possible to compare the results with independent methods that are restricted to two-dimensional flows. We describe two variants of this method: one (the ‘turbulent Ångström method’) that is better suited to laboratory experiments and a second (the ‘method of oscillatory sines’) that is effective for numerical experiments. We show that, if correctly implemented, all methods agree. Based on these results we argue that these methods can be extended to three-dimensional numerical simulations and laboratory experiments.
We apply a simple, one-equation, galaxy formation model on top of the halos and subhalos of a high-resolution dark matter cosmological simulation to study how dwarf galaxies acquire their mass and, for better mass resolution, on over 105 halo merger trees, to predict when they form their stars. With the first approach, we show that the large majority of galaxies within group- and cluster-mass halos have acquired the bulk of their stellar mass through gas accretion and not via galaxy mergers. We deduce that most dwarf ellipticals are not built up by galaxy mergers. With the second approach, we constrain the star formation histories of dwarfs by requiring that star formation must occur within halos of a minimum circular velocity set by the evolution of the temperature of the IGM, starting before the epoch of reionization. We qualitatively reproduce the downsizing trend of greater ages at greater masses and predict an upsizing trend of greater ages as one proceeds to masses lower than mcrit. We find that the fraction of galaxies with very young stellar populations (more than half the mass formed within the last 1.5 Gyr) is a function of present-day mass in stars and cold gas, which peaks at 0.5% at mcrit = 106−8M⊙, corresponding to blue compact dwarfs such as I Zw 18.
In early 2004 the Victoria Land Transect project sampled coastal north-western Ross Sea shelf benthos at Cape Adare, Cape Hallett, Cape Russell and Coulman Island from 100–500 m deep. We describe the benthic macrofaunal assemblages at these locations and, to assess the use of seafloor sediment characteristics and/or depth measures in bioregionalizations, determine the extent to which assemblage compositions are related to measured differences in these factors. Percentages of fine sand and silt, the ratio of sediment chlorophyll a to phaeophytin, and depth were identified as important explanatory variables, but in combination they explained only 17.3% of between-location differences in assemblages. Consequently, these variables are clearly not strong determinants of macrofaunal assemblage structure. Latitude per se was not a useful measure of community variability and change. A significant correlation between both number of individuals and number of taxa and sediment phaeophytin concentration across locations suggests that the distribution of the benthos reflects their response to seafloor productivity. A number of factors not measured in this study have probably influenced the structure and function of assemblages and habitats. We discuss the implications of the results to marine classifications, and stress the need to incorporate biogenic habitat complexity into protection strategies.
In order better to understand how dynamo systems saturate, we study the kinematic dynamo properties of velocity fields that arise from nonlinearly saturated dynamos. The technique is implemented by solving concurrently, in addition to the momentum equation, two induction equations, one for the actual magnetic field and one for an independent passive vector field. We apply this technique to two illustrative examples: convectively driven turbulence and turbulence represented by a shell model. In all cases we find that the velocity remains an efficient kinematic dynamo even after nonlinear saturation occurs. We discuss the implications to the process of dynamo saturation.
We consider the kinematic dynamo problem for a velocity field consisting of a mixture of turbulence and coherent structures. For these flows the dynamo growth rate is determined by a competition between the large flow structures that have large magnetic Reynolds number but long turnover times and the small ones that have low magnetic Reynolds number but short turnover times. We introduce the concept of a quick dynamo as one that reaches its maximum growth rate in some (small) neighbourhood of its critical magnetic Reynolds number. We argue that if the coherent structures are quick dynamos, the overall dynamo growth rate can be predicted by looking at those flow structures that have spatial and temporal scales such that their magnetic Reynolds number is just above critical. We test this idea numerically by studying 2.5-dimensional dynamo action which allows extreme parameter values to be considered. The required velocities, consisting of a mixture of turbulence with a given spectrum and long-lived vortices (coherent structures), are obtained by solving the active scalar equations. By using spectral filtering we demonstrate that the scales responsible for dynamo action are consistent with those predicted by the theory.
Drugs that inhibit platelet function are widely used to decrease the risk of occlusive arterial events in patients with atherosclerosis. There are three families of anti-platelet agents with proven clinical efficacy: (1) cyclo-oxygenase inhibitors, such as aspirin; (2) adenosine diphosphate receptor antagonists, such as the thienopyridine compounds ticlopidine and clopidogrel; and (3) glycoprotein IIb/IIIa antagonists. All these drugs are used during coronary interventions and in the medical management of acute coronary syndromes, while only aspirin and thienopyridine compounds are used in the long-term prevention of cardiovascular and cerebrovascular events in patients at risk. Despite the good risk-to-benefit ratio of anti-platelet agents, the risk of severe bleeding complications, including cerebral haemorrhage, is slightly increased, albeit to a much lesser extent than that associated with the use of other antithrombotic drugs, such as anticoagulants or thromobolytic agents. In addition, it must be noted that the increased incidence of haemorrhagic stroke is usually outweighed by a significant decrease in the incidence of ischaemic strokes. The combination of aspirin and vitamin K antagonists may be associated with the heightened risk of cerebral haemorrhage, compared to treatment with either drug alone.
Little information is available regarding predator-prey interactions in High-Antarctic coastal systems. In this study, the predation of Trematomus bernacchii (Pisces: Nototheniidae) on Adamussium colbecki (Mollusca: Pectinidae) is described and the related impact on the population structure of the mollusc is hypothesized. Fishes and scallops were collected during several expeditions between 1990/91 and 1997/98 summers, in nearshore waters at Terra Nova Bay (Antarctica). Adamussium colbecki was the main food item of T. bernacchii and an ontogenetic prey-size selection was observed. The predation was mainly on medium size classes of the scallop. These were lacking in the A. colbecki population sampled in the same period suggesting that the impact of fish-feeding on the size structure of the natural population of the mollusc may be substantial. Two size classes of the Adamussium population were not preyed on. Large adults avoid predation either because of the limits for mouth gape in the fish or by swimming avoidance capability, while smaller scallops may not be preyed upon because they are attached through byssus threads to very mobile large adults.