Personality differences in monozygotic twins discordant for cannabis use.

Aims: To explore the association between cannabis and personality scores when genetic background and shared environment are controlled for. Design: The co-twin control design. This design provides a powerful method for controlling for the effects of potentially confounding familial factors that may act to predispose subjects both to cannabis use and a particular personality profile. Participants: 118 monozygotic twin pairs discordant for cannabis use. Measurements: Data on personality and cannabis use were obtained through a questionnaire survey. The Dutch Sensation Seeking List was used to assess various aspects of sensation seeking. The Amsterdamse Biografische Vragenlijst assessed extraversion, neuroticism, somatic complaints and test attitude. Findings: The affected twins scored higher on all scales than their unaffected co-twins, especially on experience seeking (P = 0.004), total sensation seeking score (P = 0.004) and neuroticism (P = 0.039). Differences were also observed when items on drug use were removed from the experience seeking scale (P = 0.037) and total sensation seeking score (P = 0.009) although these differences were no longer significant after Bonferoni correction (P < 0.005). Conclusions: Cannabis use is associated with a higher score on personality scales. This result was obtained in a sample of monozygotic twins discordant for cannabis use. Thus, at least part of the association between cannabis use and experience seeking cannot be attributed to underlying genetic or shared environmental factors that influence both personality and cannabis use and must be explained by unique environmental influences. © 2007 The Authors

Hydrogel menisci: Shape, interaction, and instability

The interface of a soft hydrogel is easily deformed when it is in contact with particles, droplets or cells. Here we compute the intricate shapes of hydrogel menisci due to the indentation of point particles. The analysis is based on a free energy formulation, by which we also assess the interaction laws between neighbouring particles on hydrogel interfaces, similar to the "Cheerios effect". It is shown how the meniscus formed around the particles results from a competition between surface tension, elasticity and hydrostatic pressure inside the gel. We provide a detailed overview of the various scaling laws, which are governed by a characteristic shear modulus $G^*=\sqrt{\gamma\rho g}$ that is based on surface tension $\gamma$ and gravity $\rho g$. Stiffer materials exhibit a solid-like response while softer materials are more liquid-like. The importance of $G^*$ is further illustrated by examining the Rayleigh-Taylor instability of soft hydrogels.Comment: 7 pages, 3 figure

The central role of IL-33/IL-1RL1 pathway in asthma:From pathogenesis to intervention

Interleukin-33 (IL-33), a member of the IL-1 family, and its cognate receptor, Interleukin-1 receptor like-1 (IL-1RL1 or ST2), are susceptibility genes for childhood asthma. In response to cellular damage, IL-33 is released from barrier tissues as an & lsquo;alarmin & rsquo; to activate the innate immune response. IL-33 drives type 2 responses by inducing signalling through its receptor IL-1RL1 in several immune and structural cells, thereby leading to type 2 cytokine and chemokine production. IL-1RL1 gene transcript encodes different isoforms generated through alternative splicing. Its soluble isoform, IL-1RL1-a or sST2, acts as a decoy receptor by sequestering IL-33, thereby inhibiting IL1RL1-b/IL-33 signalling. IL-33 and its receptor IL-1RL1 are therefore considered as putative biomarkers or targets for pharmacological intervention in asthma. This review will provide an overview of the genetics and biology of the IL-33/IL-1RL1 pathway in the context of asthma pathogenesis. It will discuss the potential and complexities of targeting the cytokine or its receptor, how genetics or biomarkers may inform precision medicine for asthma targeting this pathway, and the possible positioning of therapeutics targeting IL-33 or its receptor in the expanding landscape of novel biologicals applied in asthma management. (c) 2021 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/)

Mapping social reward and punishment processing in the human brain:A voxel-based meta-analysis of neuroimaging findings using the social incentive delay task

Social rewards or punishments motivate human learning and behaviour, and alterations in the brain circuits involved in the processing of these stimuli have been linked with several neuropsychiatric disorders. However, questions still remain about the exact neural substrates implicated in social reward and punishment processing. Here, we conducted four Anisotropic Effect Size Signed Differential Mapping voxel-based meta-analyses of fMRI studies investigating the neural correlates of the anticipation and receipt of social rewards and punishments using the Social Incentive Delay task. We found that the anticipation of both social rewards and social punishment avoidance recruits a wide network of areas including the basal ganglia, the midbrain, the dorsal anterior cingulate cortex, the supplementary motor area, the anterior insula, the occipital gyrus and other frontal, temporal, parietal and cerebellar regions not captured in previous coordinate-based meta-analysis. We identified decreases in the BOLD signal during the anticipation of both social reward and punishment avoidance in regions of the default-mode network that were missed in individual studies likely due to a lack of power. Receipt of social rewards engaged a robust network of brain regions including the ventromedial frontal and orbitofrontal cortices, the anterior cingulate cortex, the amygdala, the hippocampus, the occipital cortex and the brainstem, but not the basal ganglia. Receipt of social punishments increased the BOLD signal in the orbitofrontal cortex, superior and inferior frontal gyri, lateral occipital cortex and the insula. In contrast to the receipt of social rewards, we also observed a decrease in the BOLD signal in the basal ganglia in response to the receipt of social punishments. Our results provide a better understanding of the brain circuitry involved in the processing of social rewards and punishment. Furthermore, they can inform hypotheses regarding brain areas where disruption in activity may be associated with dysfunctional social incentive processing during diseas

Early posttraumatic autonomic and endocrine markers to predict posttraumatic stress symptoms after a preventive intervention with oxytocin

Background: Efficient prevention of posttraumatic stress disorder (PTSD) needs to target individuals with an increased risk for adverse outcome after trauma. Prognostic or prescriptive biological markers assessed early posttrauma may inform personalized treatment recommendations. Objective: To test prognostic and prescriptive effects of early (posttraumatic) autonomic and endocrine markers on PTSD symptom development. Method: Autonomic and endocrine markers were assessed within 12 days posttrauma and before treatment initiation within a randomized placebo-controlled trial investigating repeated oxytocin administration as preventive intervention for PTSD. Linear mixed effects models were used to test the effects of heart rate (variability), resting cortisol, morning cortisol and cortisol awakening response (CAR), cortisol suppression by dexamethasone and resting oxytocin on PTSD symptoms 1.5, 3 and 6 months posttrauma in men (n = 54), women using hormonal contraception (n = 27) and cycling women (n = 19). Results: We found significant prognostic effects of resting oxytocin and cortisol suppression. In women using hormonal contraception, higher oxytocin was associated with higher PTSD symptoms across follow-up. Stronger cortisol suppression by dexamethasone, reflecting increased glucocorticoid receptor feedback sensitivity, was associated with lower PTSD symptoms across follow-up in men, but with higher symptoms at 1.5 months in women using hormonal contraception. These effects were independent of treatment condition. No further significant prognostic or prescriptive effects were detected. Conclusion: Our exploratory study indicates that resting oxytocin and glucocorticoid receptor feedback sensitivity early posttrauma are associated with subsequent PTSD symptom severity. Notably, prognostic effects depended on sex and hormonal contraception use, emphasizing the necessity to consider these factors in biomedical PTSD research

How childhood trauma and recent adverse events are related to hair cortisol levels in a large adult cohort

Background: Exposure to adversity is a risk factor for many mental and somatic health problems. Hypothalamic-pituitary-adrenal (HPA) axis dysregulation is a potential mechanism linking adversity exposure and negative health outcomes. However, associations between adversity exposure and HPA-axis activity have been inconsistent. To understand the impact of adversity on the HPA-axis, we examined associations between early-life and recent adversity with hair cortisol concentration, an indicator of long-term systemic cortisol levels. Methods: We included 1166 adult participants of the Netherlands Study of Depression and Anxiety (NESDA). Hair cortisol was measured in 3 cm of proximal hair, representing cortisol exposure during the previous 3 months. Childhood maltreatment, childhood negative life events, and recent negative life events were retrospectively assessed using interview and self-report questionnaires. Linear regression analyses were performed to assess the associations between childhood maltreatment, childhood life events and recent life events with hair cortisol. Associations with cumulative adversity exposure and with subtypes of childhood maltreatment, childhood and recent negative life events were also investigated, as were interaction effects between adversity and sex, age and psychopathology. Results: Childhood maltreatment (β = 0.034, p = 0.243), childhood

Happiness through leisure

Happiness is important to individuals. If one were to make a judgment based on the vast amount of self-help books available in any bookstore, the conclusion would have to be that happiness is a very important aspect of people’s lives. Whether such books actually provide any solutions to increase happiness is doubtful (Bergsma, 2008). Nevertheless, many are clearly interested in happiness