Nuclear Magnetic Relaxation Times of Mn⁵⁵ in Dilute MnFe Alloys

Nuclear magnetic relaxation times (T₁ and T₂) were measured in dilute MnFe alloys. The relaxation processes are effected by the Mn-impurity and related by the functions with impurity concentrations.Article信州大学理学部紀要 10(2): 81-84(1976)departmental bulletin pape

Longitudinal impact of the COVID-19 pandemic on the development of mental disorders in preadolescents and adolescents

Background　School closures and social distancing may have affected mental health among preadolescent and adolescent children, who are in a social developmental stage. Rates of anxiety, depression, and stress have been reported to have increased during the COVID-19 pandemic among teenagers worldwide. However, most studies have measured children's mental health in cross-sectional studies or short-term comparisons before and after lockdowns and school closures, and few studies have tracked the long-term effects on mental health among children and adolescents, despite the pandemic lasting more than 2 years. Methods　An interrupted time-series analysis was performed for longitudinal changes in the monthly number of new mental disorders (eating disorders, schizophrenia, mood disorders, and somatoform disorders). Using a nationwide multicenter electronic health records database in Japan, we analyzed data of patients aged 9 to 18 years from 45 facilities that provided complete data throughout the study period. The study period covered January 2017 to May 2021, defining a national school closure as an intervention event. We modeled the monthly new diagnoses of each mental disorder using a segmented Poisson regression model. Results　The number of new diagnoses throughout the study period was 362 for eating disorders, 1104 for schizophrenia, 926 for mood disorders, and 1836 for somatoform disorders. The slope of the regression line in monthly number of new diagnoses increased in the post-pandemic period for all targeted mental disorders (change in slope for eating disorders 1.05, 95% confidence interval [CI] 1.00-1.11; schizophrenia 1.04, 95% CI 1.01-1.07; mood disorders 1.04, 95% CI 1.01-1.07; and somatoform disorders 1.04 95% CI 1.02-1.07). The number of new diagnoses for schizophrenia and mood disorders increased early after school closure; while eating disorders showed an increasing trend several months later. Somatoform disorders showed a decreasing trend followed by an increasing trend. Time trends by sex and age also differed for each mental disorder. Conclusions　In the post-pandemic period, the number of new cases increased over time for eating disorders, schizophrenia, mood disorders, and somatoform disorders. The timing of increase and trends by sex and age differed for each mental disorder

Metallic phase in the metal-intercalated higher fullerene Rb8.8(7)C84

A new material of higher fullerene, RbxC84, was synthesized by intercalating Rb metal into C-84 crystals. The RbxC(84) crystals showed a simple cubic (sc) structure with lattice constant, a, of 16.82 (2) angstrom at 6.5 K, and 16.87 (2) angstrom at 295 K. The Rietveld refinements were achieved with the space group, Pa (3) over bar, based on a model that the C-2 axis of D2d-C84 aligned along [111]. The sample composition was determined to be Rb-8.8(7) C-84. The ESR spectrum at 303 K was composed of a broad peak with peak-to-peak linewidth Delta H-pp of 220 G, and a narrow peak with Delta H-pp of 24 G. Temperature dependence of the broad peak clearly showed a metallic behavior. The metallic behavior was discussed based on a theoretical calculation. This finding of new metallic phase in a higher fullerene is the first step for a development of new types of fullerene materials with novel physical properties such as superconductivity.</p

Quality of life and physical/psychosocial factors in children and adolescents with orthostatic intolerance

Background　Orthostatic intolerance (OI), which is common in children and adolescents, negatively impacts their quality of life (QOL) due to physical symptoms that limit work, school, and daily activities. The purpose of this study is to explore the association of physical and psychosocial factors with QOL scores in children and adolescents with OI. Methods　A cross sectional observational study was conducted. The study participants included 95 Japanese pediatric patients of age 9-15 years who were diagnosed with OI from April 2010 to March 2020. The QOL scores and the QOL T-scores of children with OI assessed using the KINDL-R questionnaire at the initial visit were compared with conventional normative data. The associations of physical and psychosocial factors with the QOL T-scores were examined using multiple linear regression. Results　Pediatric patients with OI had significantly lower QOL scores than healthy children in both elementary (50.7 +/- 13.5 vs. 67.9 +/- 13.4, p Conclusions　These results suggest that the assessment of QOL, including both physical and psychosocial aspects, especially school factors, needs to be implemented earlier in children and adolescents with OI

Rap1 translates chemokine signals to integrin activation, cell polarization, and motility across vascular endothelium under flow

Chemokines arrest circulating lymphocytes within the vasculature through the rapid up-regulation of leukocyte integrin adhesive activity, promoting subsequent lymphocyte transmigration. However, the key regulatory molecules regulating this process have remained elusive. Here, we demonstrate that Rap1 plays a pivotal role in chemokine-induced integrin activation and migration. Rap1 was activated by secondary lymphoid tissue chemokine (SLC; CCL21) and stromal-derived factor 1 (CXCL4) treatment in lymphocytes within seconds. Inhibition of Rap1 by Spa1, a Rap1-specific GTPase-activating protein, abrogated chemokine-stimulated lymphocyte rapid adhesion to endothelial cells under flow via intercellular adhesion molecule 1. Expression of a dominant active Rap1V12 in lymphocytes stimulated shear-resistant adhesion, robust cell migration on immobilized intercellular adhesion molecule 1 and vascular cell adhesion molecule 1, and transendothelial migration under flow. We also demonstrated that Rap1V12 expression in lymphocytes induced a polarized morphology, accompanied by the redistribution of CXCR4 and CD44 to the leading edge and uropod, respectively. Spa1 effectively suppressed this polarization after SLC treatment. This unique characteristic of Rap1 may control chemokine-induced lymphocyte extravasation

Cellular Polyamine Catalogues of the Five Classes of the PhylumProteobacteria: Distributions of Homospermidine within the ClassAlphaproteobacteria, Hydroxyputrescine within the ClassBetaproteobacteria, Norspermidine within the ClassGammaproteobacteria, and Spermine within the ClassesDeltaproteobacteria and Epsilonproteobacteria

Cellular polyamines extracted from reclassified or newly validated 47 alphaproteobacteria, 46 betaproteobacteria, 96 gammaproteobacteria, 12 deltaproteobacteria and 10 epsilonproteobacteria were analyzed by high-performance liquid chromatography. Homospermidine was widely distributed within the class Alphaproteobacteria, however, homospermidine-dominant type, spermidine-dominant type and homospermidine/spermidinedominant type were found and the three triamine profiles were genus-specific. The all genera belonging to the class Betaproteobacteria, ubiquitously contained putrescine and 2- hydroxyputrescine. Triamines were absent in almost betaproteobacteria. Many genera, including psychrophilic species, of the class Gammaproteobacteria, contained putrescine and spermidine as the major polyaminenes. Diaminopropane and norspermidine were selectively distributed in several genera of the class Gammaproteobacteria. Spermidine was the major polyamine in the classes Deltaproteobacteria and Epsilonproteobacteria. Spermine was found in some thermophiles within Betaproteobacteria, Deltaproteobacteria and Epsilonproteobacteria, suggesting that the occurrence of spermine correlate to their thermophily. Additional these polyamine catalogues serve for the classification of the phylum Proteobacteria, as a chemotaxonomic marker

Viral RNA recognition by LGP2 and MDA5, and activation of signaling through step-by-step conformational changes

細胞内のウイルスを認識する蛋白質の仕組みを解明 --ウイルスから我々の体を守る影のヒーロー--. 京都大学プレスリリース. 2020-12-04.Cytoplasmic RIG-I-like receptor (RLR) proteins in mammalian cells recognize viral RNA and initiate an antiviral response that results in IFN-β induction. Melanoma differentiation-associated protein 5 (MDA5) forms fibers along viral dsRNA and propagates an antiviral response via a signaling domain, the tandem CARD. The most enigmatic RLR, laboratory of genetics and physiology (LGP2), lacks the signaling domain but functions in viral sensing through cooperation with MDA5. However, it remains unclear how LGP2 coordinates fiber formation and subsequent MDA5 activation. We utilized biochemical and biophysical approaches to observe fiber formation and the conformation of MDA5. LGP2 facilitated MDA5 fiber assembly. LGP2 was incorporated into the fibers with an average inter-molecular distance of 32 nm, suggesting the formation of hetero-oligomers with MDA5. Furthermore, limited protease digestion revealed that LGP2 induces significant conformational changes on MDA5, promoting exposure of its CARDs. Although the fibers were efficiently dissociated by ATP hydrolysis, MDA5 maintained its active conformation to participate in downstream signaling. Our study demonstrated the coordinated actions of LGP2 and MDA5, where LGP2 acts as an MDA5 nucleator and requisite partner in the conversion of MDA5 to an active conformation. We revealed a mechanistic basis for LGP2-mediated regulation of MDA5 antiviral innate immune responses