Subthreshold depression (StD) is associated an increased risk of developing major depressive disorder (MDD) and suicidality. Suicidality could be linked to distress intolerance and use of ...context-dependent strategies. We identified neural correlates of executive functioning among the hubs in the resting-state functional connectome (rs-FCN) and examined associations with recent suicidality in StD and MDD. In total, 79 young adults 27 StD, 30 MDD, and 23 healthy controls (HC) were scanned using magnetic resonance imaging. Neurocognitive measures of the mean latency to correct five moves in the One Touch Stockings of Cambridge (OTSMLC5), spatial working memory between errors (SWMBE), rapid visual information processing A' (RVPA'), and the stop signal reaction time in the stop signal test (SSTSSRT) were obtained. Global graph metrics were calculated to measure the network integration, segregation, and their balance in the rs-FCN. Regional graph metrics reflecting the number of neighbors (degree centrality; DC), participation in the shortcuts (betweenness centrality; BC), and accessibility to intersections (eigenvector centrality; EC) in the rs-FCN defined group-level hubs for StD, HC, and MDD, separately. Global network metrics were comparable among the groups (all P > 0.05). Among the group-level hubs, regional graph metrics of left dorsal anterior insula (dAI), right dorsomedial prefrontal cortex (dmPFC), right rostral temporal thalamus, right precuneus, and left postcentral/middle temporal/anterior subgenual cingulate cortices were different among the groups. Further, significant associations with neurocognitive measures were found in the right dmPFC with SWMBE, and left dAI with SSTSSRT and RVPA'. Shorter OTSMLC5 was related to the lower centralities of right thalamus and suffer of recent 1-year suicidal ideation (all Ps < 0.05 in ≥ 2 centralities out of DC, BC, and EC). Collectively, salience and thalamic networks underlie spatial strategy and planning, response inhibition, and suicidality in StD and MDD. Anti-suicidal therapies targeting executive function and modulation of salience-thalamic network in StD and MDD are required.
Fibromyalgia (FM) and complex regional pain syndrome (CRPS) share many pathological mechanisms related to chronic pain and neuroinflammation, which may contribute to the multifactorial pathological ...mechanisms in both FM and CRPS. The aim of this study was to assess neuroinflammation in FM patients compared with that in patients with CRPS and healthy controls.
Neuroinflammation was measured as the distribution volume ratio (DVR) of 11C-(R)-PK11195 positron emission tomography (PET) in 12 FM patients, 11 patients with CRPS and 15 healthy controls.
Neuroinflammation in FM patients was significantly higher in the left pre (primary motor cortex) and post (primary somatosensory cortex) central gyri (p < 0.001), right postcentral gyrus (p < 0.005), left superior parietal and superior frontal gyri (p < 0.005), left precuneus (p < 0.01), and left medial frontal gyrus (p = 0.036) compared with healthy controls. Furthermore, the DVR of 11C-(R)-PK11195 in FM patients demonstrated decreased neuroinflammation in the medulla (p < 0.005), left superior temporal gyrus (p < 0.005), and left amygdala (p = 0.020) compared with healthy controls.
To the authors' knowledge, this report is the first to describe abnormal neuroinflammation levels in the brains of FM patients compared with that in patients with CRPS using 11C-(R)-PK11195 PET. The results suggested that abnormal neuroinflammation can be an important pathological factor in FM. In addition, the identification of common and different critical regions related to abnormal neuroinflammation in FM, compared with patients with CRPS and healthy controls, may contribute to improved diagnosis and the development of effective medical treatment for patients with FM.
Background Previous neuroimaging studies of obsessive-compulsive disorder (OCD) have reported both baseline functional alterations and pharmacological changes in localized brain regions and ...connections; however, the effects of selective serotonin reuptake inhibitor (SSRI) treatment on the whole-brain functional network have not yet been elucidated. Methods Twenty-five drug-free OCD patients underwent resting-state functional magnetic resonance imaging. After 16-weeks, seventeen patients who received SSRI treatment were rescanned. Twenty-three matched healthy control subjects were examined at baseline for comparison, and 21 of them were rescanned after 16 weeks. Topological properties of brain networks (including small-world, efficiency, modularity, and connectivity degree) were analyzed cross-sectionally and longitudinally with graph-theory approach. Results At baseline, OCD patients relative to healthy control subjects showed decreased small-world efficiency (including local clustering coefficient, local efficiency, and small-worldness) and functional association between default-mode and frontoparietal modules as well as widespread altered connectivity degrees in many brain areas. We observed clinical improvement in OCD patients after 16 weeks of SSRI treatment, which was accompanied by significantly elevated small-world efficiency, modular organization, and connectivity degree. Improvement of obsessive-compulsive symptoms was significantly correlated with changes in connectivity degree in right ventral frontal cortex in OCD patients after treatment. Conclusions This is first study to use graph-theory approach for investigating valuable biomarkers for the effects of SSRI on neuronal circuitries of OCD patients. Our findings suggest that OCD phenomenology might be the outcome of disrupted optimal balance in the brain networks and that reinstating this balance after SSRI treatment accompanies significant symptom improvement.
Mind-body training (MBT) programs are effective interventions for relieving stress and improving psychological capabilities. To expand our previous study which demonstrated the short-term effects of ...an 8-week online MBT program, the present study investigated whether those short-term effects persist up to a month after the end of the intervention.Among previous participants, 56 (64%) participated in this follow-up study, 25 in the MBT group and 31 in the control group. Outcome measures included the stress response, emotional intelligence, resilience, coping strategies, positive and negative affect, and anger expression of both groups at baseline, at 8 weeks (right after the training or waiting period), and at 12 weeks (a month after the training or waiting period).The MBT group showed a greater decrease in stress response at 8 weeks, and this reduction remained a month after the end of the intervention. The effect of MBT on resilience and effective coping strategies was also significant at 8 weeks and remained constant a month later. However, the improvement to emotional intelligence and negative affect did not persist a month after training.These findings suggest that the beneficial short-term effects of MBT may last beyond the training period even without continuous practice, but the retention of these benefits seems to depend on the outcome variables. Through a convenient, affordable, and easily accessible online format, MBT may provide cost-effective solutions for employees at worksites.
As the main input hub of the basal ganglia, the striatum receives projections from the cerebral cortex. Many studies have provided evidence for multiple parallel corticostriatal loops based on the ...structural and functional connectivity profiles of the human striatum. A recent resting-state fMRI study revealed the topography of striatum by assigning each voxel in the striatum to its most strongly correlated cortical network among the cognitive, affective, and motor networks. However, it remains unclear what patterns of striatal parcellation would result from performing the clustering without subsequent assignment to cortical networks. Thus, we applied unsupervised clustering algorithms to parcellate the human striatum based on its functional connectivity patterns to other brain regions without any anatomically or functionally defined cortical targets. Functional connectivity maps of striatal subdivisions, identified through clustering analyses, were also computed. Our findings were consistent with recent accounts of the functional distinctions of the striatum as well as with recent studies about its functional and anatomical connectivity. For example, we found functional connections between dorsal and ventral striatal clusters and the areas involved in cognitive and affective processes, respectively, and between rostral and caudal putamen clusters and the areas involved in cognitive and motor processes, respectively. This study confirms prior findings, showing similar striatal parcellation patterns between the present and prior studies. Given such striking similarity, it is suggested that striatal subregions are functionally linked to cortical networks involving specific functions rather than discrete portions of cortical regions. Our findings also demonstrate that the clustering of functional connectivity patterns is a reliable feature in parcellating the striatum into anatomically and functionally meaningful subdivisions. The striatal subdivisions identified here may have important implications for understanding the relationship between corticostriatal dysfunction and various neurodegenerative and psychiatric disorders.
Various supraparticles have been extensively studied owing to their excellent catalytic properties that are attributed to their inherent porous structure; however, their mechanical properties have ...not garnered attention owing to their less dense structure. We demonstrate a rational approach for fabricating assembled supraparticles and, subsequently, highly dense microspheres. In addition, 3 mol % yttria-stabilized zirconia (3YSZ) and alumina particles were selected as building blocks and assembled into higher-order architectures using a droplet-based template method (spray drying) for validation with proof-of-concept. Moreover, structural features such as density, size, sphericity, and morphology of supraparticles were controlled by adjusting the competing kinetics occurring between the assembly of building blocks and evaporation of the solvent in the droplets. The preparatory aqueous suspension and process parameters were optimized as well. A detailed understanding of the formation mechanism facilitated the yield of tailor-made supraparticles and, thereafter, highly dense microspheres (approximate relative density = 99%) with excellent sphericity (>98%) via heat treatment. The microspheres displayed highest hardness (26.77 GPa) and superior elastic modulus (210.19 GPa) compared with the mechanical properties of the 3YSZ samples reported to date. Ultimately, the proposed supraparticle engineering provided insight for controlling the structural features and resultant micromechanical properties, which widely extends the applicability of supraparticle-based functional materials for practical purposes that require materials with high density and excellent mechanical properties.
▶ The default mode network and brain areas associated with meditation have similarities. ▶ Meditators showed greater functional connectivity in the medial prefrontal cortex. ▶ Long-term practice of ...meditation may be associated with functional changes in brains.
Areas associated with the default mode network (DMN) are substantially similar to those associated with meditation practice. However, no studies on DMN connectivity during resting states have been conducted on meditation practitioners. It was hypothesized that meditators would show heightened functional connectivity in areas of cortical midline activity. Thirty-five meditation practitioners and 33 healthy controls without meditation experience were included in this study. All subjects received 4.68-min resting state functional scanning runs. The posterior cingulate cortex and medial prefrontal cortex were chosen as seed regions for the DMN map. Meditation practitioners demonstrated greater functional connectivity within the DMN in the medial prefrontal cortex area (xyz=339−21) than did controls. These results suggest that the long-term practice of meditation may be associated with functional changes in regions related to internalized attention even when meditation is not being practiced.
Given that the insula plays a contributory role in the perception of chronic pain, we examined the resting-state functional connectivity between the insular cortex and other brain regions to ...investigate neural underpinnings of persisting perception of background pain in patients with complex regional pain syndrome (CRPS). A total of 25 patients with CRPS and 25 matched healthy controls underwent functional magnetic resonance imaging at rest. With the anterior and posterior insular cortices as seed regions, we compared the strength of the resting-state functional connectivity between the two groups. Functional connectivity between the anterior and posterior insular cortices and the postcentral and inferior frontal gyri, cingulate cortices was reduced in patients with CRPS compared with controls. Additionally, greater reductions in functional connectivity between the anterior insula and right postcentral gyrus were associated with more severe sensory pain in patients with CRPS (short-form McGill Pain Questionnaire sensory subscores, r = -.517, P = .023). The present results imply a possible role of the insula in aberrant processing of pain information in patients with CRPS. The findings suggest that a functional derangement of the connection between one of the somatosensory cortical functions of perception and one of the insular functions of awareness can play a significant role in the persistent experience of regional pain that is not confined to a specific nerve territory.
Subthreshold depression (StD) is associated with higher risk of later developing major depressive disorder (MDD). Deficits of goal-directed behaviors regarding the motional, motivational, and ...conflict control are found in MDD. The current study examined neural underpinning of conflict control against monetary punishment in StD compared to MDD and healthy controls (HC). Seventy-one participants (HC, n = 27; StD, n = 21; MDD, n = 23) in their mid-20's completed self-reports. Preprocessing of functional magnetic resonance imaging acquired for the Simon task against larger or smaller monetary punishment was conducted using ENIGMA HALFpipe version 1.2.1. Neural correlates of conflict control against monetary punishment that could vary with either diagnosis or PHQ-9 total score were examined using a general linear model of FSL. Simon effect was effective for reaction time and accuracy in every subgroup of diagnosis and regardless of the size of monetary punishment. Conflict control against larger monetary loss was associated with higher functional activation of left insula in StD than HC and MDD. StD showed lower functional activation of left dorsal anterior cingulate (dACC) than MDD for conflict control against larger monetary loss. For conflict control against smaller monetary loss, StD demonstrated higher functional activation of left paracentral lobule and right putamen compared to HC. Directed acyclic graphs showed directional associations from suicidal ideation, sadness, and concentration difficulty to functional activation of paracentral lobule, ventromedial prefrontal cortex (vmPFC), and thalamus for conflict control against monetary loss. Differential functional activation of insula and dACC for conflict control against larger monetary loss could be a brain phenotype of StD. Item-level depressive symptoms of suicidal ideation, sadness, and concentration difficulty could be reflected in the conflict control-related functional activation of paracentral lobule (against smaller monetary loss), vmPFC and thalamus (against larger monetary loss), respectively.
This study investigated MnFe0.95-xNixP0.5-ySi0.5+y (0.01 ≤ x ≤ 0.16, −0.05 ≤ y ≤ 0.1) alloys prepared by arc melting. The alloys were crystallized in a typical Fe2P-type hexagonal main phase. They ...exhibited strong coupling between lattice variation and magnetic transition, which is the major factor in the large magnetocaloric properties. The effects of coupling were observed from two perspectives: Fe-Ni substitution for transition temperature tuning and P/Si ratio for reducing the amount of expensive P alloy. For the Fe - Ni substitution, the transition temperature decreased by about 7.8 K per 0.01 Ni contents (x). In the case of the P/Si ratio control, a secondary phase was generated based on the increase in Si content. The alloys showed maximum magnetic entropy change (∆SMmax) ranging from 8.65 to 17.22 J kg−1 K−1 for the applied magnetic field 2 T in the temperature range from 214 K to 335 K. For the MnFe0.91Ni0.04P0.45Si0.55 alloy with a low P/Si ratio, the ∆SMmax was 15.32 J kg−1 K−1 for the applied magnetic field 2 T at 304 K close to room temperature. This demonstrates that the alloys with large magnetocaloric properties in this research are competitive to other known magnetic refrigeration materials.
•Magnetocaloric properties in conjunction with lattice variations of (Mn, Fe, Ni)2(P, Si) alloys were investigated.•MnFe0.91Ni0.04P0.5Si0.5 exhibits a magnetoelastic coupling at about 302 K.•As in Fig.2(c), Tc of the alloys decreases linearly with increasing Ni content.•The maximum ∆SM was recorded of 17.22 J kg− 1·K at 2 T comparable to other candidates targeting room temperature usage.
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