140 research outputs found

    Sc2C, a 2D Semiconducting Electride

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    Electrides are exotic materials that typically have electrons present in well-defined lattice sites rather than within atoms. Although all known electrides have an electropositive metal cation adjacent to the electride site, the effect of cation electronegativity on the properties of electrides is not yet known. Here, we examine trivalent metal carbides with varying degrees of electronegativity and experimentally synthesize Sc2C. Our studies identify the material as a two-dimensional (2D) electride, even though Sc is more electronegative than any metal previously found adjacent to an electride site. Further, by exploring Sc2C and Al2C computationally, we find that higher electronegativity of the cation drives greater hybridization between metal and electride orbitals, which opens a band gap in these materials. Sc2C is the first 2D electride semiconductor, and we propose a design rule that cation electronegativity drives the change in its band structure

    Restoring function to inactivating G protein-coupled receptor variants in the hypothalamic–pituitary–gonadal axis1

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    DATA AVAILABILITY STATEMENT : Data sharing is not applicable to this article as no new data were created or analysed in this study.G protein-coupled receptors (GPCRs) are central to the functioning of the hypothalamic–pituitary–gonadal axis (HPG axis) and include the rhodopsin-like GPCR family members, neurokinin 3 receptor, kappa-opioid receptor, kisspeptin 1 receptor, gonadotropin-releasing hormone receptor, and the gonadotropin receptors, luteinizing hormone/choriogonadotropin receptor and follicle-stimulating hormone receptor. Unsurprisingly, inactivating variants of these receptors have been implicated in a spectrum of reproductive phenotypes, including failure to undergo puberty, and infertility. Clinical induction of puberty in patients harbouring such variants is possible, but restoration of fertility is not always a realisable outcome, particularly for those patients suffering from primary hypogonadism. Thus, novel pharmaceuticals and/or a fundamental change in approach to treating these patients are required. The increasing wealth of data describing the effects of coding-region genetic variants on GPCR function has highlighted that the majority appear to be dysfunctional as a result of misfolding of the encoded receptor protein, which, in turn, results in impaired receptor trafficking through the secretory pathway to the cell surface. As such, these intracellularly retained receptors may be amenable to ‘rescue’ using a pharmacological chaperone (PC)-based approach. PCs are small, cell permeant molecules hypothesised to interact with misfolded intracellularly retained proteins, stabilising their folding and promoting their trafficking through the secretory pathway. In support of the use of this approach as a viable therapeutic option, it has been observed that many rescued variant GPCRs retain at least a degree of functionality when ‘rescued’ to the cell surface. In this review, we examine the GPCR PC research landscape, focussing on the rescue of inactivating variant GPCRs with important roles in the HPG axis, and describe what is known regarding the mechanisms by which PCs restore trafficking and function. We also discuss some of the merits and obstacles associated with taking this approach forward into a clinical setting.The National Research Foundation, South Africa.http://wileyonlinelibrary.com/journal/jnehj2024ImmunologyPhysiologySDG-03:Good heatlh and well-bein

    Brain activation of the defensive and appetitive survival systems in obsessive compulsive disorder

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    Several studies have shown that basic emotions are responsible for a significant enhancement of early visual processes and increased activation in visual processing brain regions. It may be possible that the cognitive uncertainty and repeated behavioral checking evident in Obsessive Compulsive Disorder (OCD) is due to the existence of abnormalities in basic survival circuits, particularly those associated with the visual processing of the physical characteristics of emotional-laden stimuli. The objective of the present study was to test if patients with OCD show evidence of altered basic survival circuits, particularly those associated with the visual processing of the physical characteristics of emotional stimuli. Fifteen patients with OCD and 12 healthy controls underwent functional magnetic resonance imaging acquisition while being exposed to emotional pictures, with different levels of arousal, intended to trigger the defensive and appetitive basic survival circuits. Overall, the present results seem to indicate dissociation in the activity of the defense and appetitive survival systems in OCD. Results suggest that the clinical group reacts to basic threat with a strong activation of the defensive system mobilizing widespread brain networks (i.e., frontal, temporal, occipital-parietal, and subcortical nucleus) and blocking the activation of the appetitive system when facing positive emotional triggers from the initial stages of visual processing (i.e., superior occipital gyrus)

    When it's at: An examination of when cognitive change occurs during cognitive therapy for compulsive checking in obsessive-compulsive disorder

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    Abstract Background and objectives The cognitive theory of compulsive checking in OCD proposes that checking behaviour is maintained by maladaptive beliefs, including those related to inflated responsibility and those related to reduced memory confidence. This study examined whether and when specific interventions (as part of a new cognitive therapy for compulsive checking) addressing these cognitive targets changed feelings of responsibility and memory confidence. Methods Participants were nine adults with a primary or secondary diagnosis of OCD who reported significant checking symptoms (at least one hour per day) on the Yale-Brown Obsessive-Compulsive Scale. A single-case multiple baseline design was used, after which participants received 12 sessions of cognitive therapy. From the start of the baseline period through to the 1 month post-treatment follow-up assessment session, participants completed daily monitoring of feelings of responsibility, memory confidence, and their time spent engaging in compulsive checking. Results Results revealed that feelings of responsibility significantly reduced and memory confidence significantly increased from baseline to immediately post-treatment, with very high effect sizes. Multilevel modelling revealed significant linear changes in feelings of responsibility (i.e., reductions over time) and memory confidence (i.e., increases over time) occurred following the sessions when these were addressed. Finally, we found that improvements in these over the course of the treatment significantly predicted reduced time spent checking. Limitations The small sample size limits our ability to generalize our results. Conclusions Results are discussed in terms of a focus on the timing of change in cognitive therapy

    Autism and ADHD Symptoms in Patients with OCD: Are They Associated with Specific OC Symptom Dimensions or OC Symptom Severity?

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    In obsessive-compulsive disorder (OCD), the relationship between autism spectrum disorders (ASD), attention-deficit/hyperactivity disorder (ADHD) symptom, and obsessive-compulsive (OC) symptom dimensions and severity has scarcely been studied. Therefore, 109 adult outpatients with primary OCD were compared to 87 healthy controls on OC, ADHD and ASD symptoms. OCD patients showed increased ADHD and autism symptom frequencies, OCD + ADHD patients reporting more autism symptoms (particularly attention switching and social skills problems) than OCD − ADHD patients. Attention switching problems were most significant predictors of OC symptom dimensions (except hoarding) and of symptom severity. Hoarding was not associated with elevated autism scale scores, but with inattention. In conclusion, attention switching problems may reflect both symptom overlap and a common etiological factor underlying ASD, ADHD and OCD
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