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In general, negative thermal expansion (NTE) is entropy-driven. We have developed the alternative approach for achieving uniaxial NTE in a molecular crystal induced by supramolecular deformation and molecular rotation, along with peculiar magnetic responses. In the crystal of (pyridazinium+)2(dibenzo[24]crown-8)3[Ni(dmit)2]−2 (1) (dmit = 1,3-dithiole-2-thione-4,5-dithiolate), pyridazinium was included within the dibenzo[24]crown-8, and formed a one-dimensional columnar structure parallel to the a-axis. This column elongates along the a-axis, and shrinks along the b-axis. This provides space for the pyridazinium to rotate, which promotes further NTE above 183 K. In addition, the [Ni(dmit)2]− forms a dimer, where the intradimer magnetic exchange interaction (J) increases with increasing temperature. The modified singlet–triplet thermal excitation model, where J increased with increasing temperature, can be fitted to the temperature-dependent magnetic susceptibility of 1. A deviation from the model was observed above 180 K, which is attributed to the structural changes within the [Ni(dmit)2]− dimer, caused by the molecular rotation of the pyridazinium moiety. [ABSTRACT FROM AUTHOR]

Background: Previous studies have identified noninvasive methods for predicting atrial fibrillation (AF) recurrence after catheter ablation (CA). We assessed the association between AF recurrence and atrial late potentials (ALPs), which were measured using P‐wave signal‐averaged electrocardiography (P‐SAECG). Methods: Consecutive patients with paroxysmal AF who underwent their first CA at our institution between August 2015 and August 2019 were enrolled. P‐SAECG was performed before CA. Two ALP parameters were evaluated: the root‐mean‐square voltage during the terminal 20 ms (RMS20) and the P‐wave duration (PWD). Positive ALPs were defined as an RMS20 <2.2 μV and/or a PWD >115 ms. Patients were allocated to either the recurrence or nonrecurrence group based on the presence of AF recurrence at the 1‐year follow‐up post‐CA. Results: Of the 190 patients (age: 65 ± 11 years, 37% women) enrolled in this study, 21 (11%) had AF recurrence. The positive ALP rate was significantly higher in the recurrence group than in the nonrecurrence group (86% vs. 64%, p =.04), despite the absence of differences in other baseline characteristics between the two groups. In the multivariate analysis, positive ALP was an independent predictor of AF recurrence (odds ratio: 3.83, 95% confidence interval: 1.05–14.1, p =.04). Conclusions: Positive ALP on pre‐CA P‐SAECG is associated with AF recurrence after CA. [ABSTRACT FROM AUTHOR]

Background: Although the lesion size index (LSI) has been well established, it is sometimes difficult to achieve first‐pass pulmonary vein isolation (PVI) and to avoid acute pulmonary vein reconnections, even with LSI‐guided procedures. The purpose of this study was to assess the predictive accuracy of a novel parameter, the optimized lesion size index (o‐LSI), to perform PVI. Methods: The voltage maps created by the Advisor™ high‐density (HD) grid catheter before PVI in 35 atrial fibrillation (AF) patients were examined for an association between the voltage amplitude and insufficient ablation sites (IAS), which were defined as either (i) spontaneous reconnection sites, (ii) dormant PV conduction sites unmasked with 20 mg of adenosine triphosphate disodium hydrate (ATP) injection, or (iii) PV‐LA gap sites after the initial PVI. Results: IAS was observed in 25/1417 of the total ablation sites. IAS was significantly associated with higher bipolar voltage areas (4.20 ± 2.68 vs 2.43 ± 1.93 mV, P <.0001) but not with LSI. A novel index, o‐LSI (defined as LSI/bipolar voltage), was significantly lower in IAS than in others (1.14 [0.82, 1.81] vs 2.35 [1.31, 4.80] LSI/mV). By receiver operating characteristic analysis, an o‐LSI of 2.04 was the best cutoff value for the prediction of IAS (88% sensitivity and 55% specificity, P <.0001, areas under the curve: 0.742). Conclusion: Low o‐LSI was strongly associated with IAS, potentially providing a novel index to improve first‐pass PV isolation. [ABSTRACT FROM AUTHOR]

Background: Right ventricular (RV) pacing causes left ventricular (LV) dyssynchrony sometimes resulting in pacing‐induced cardiomyopathy. However, RV pacing for hypertrophic obstructive cardiomyopathy is one of the treatment options. LV flow energy loss (EL) using vector flow mapping (VFM) is a novel hemodynamic index for assessing cardiac function. Our study aimed to elucidate the impact of RV pacing on EL in normal LV function and hypertrophic cardiomyopathy (HCM) patients. Methods: A total of 36 patients with dual‐chamber pacemakers for sick sinus syndrome or implantable cardioverter defibrillators for fatal ventricular tachyarrhythmias were enrolled. All patients were divided into two groups: 16 patients with HCM (HCM group) and others (non‐HCM group). The absolute changes in EL under AAI (without RV pacing) and DDD (with RV pacing) modes were assessed using VFM on color Doppler echocardiography. Results: In the non‐HCM group, the mean systolic EL significantly increased from the AAI to DDD modes (14.0 ± 7.7 to 17.0 ± 8.6 mW/m, P =.003), whereas the mean diastolic EL did not change (19.0 ± 12.3 to 17.0 ± 14.8 mW/m, P =.231). In the HCM group, the mean systolic EL significantly decreased from the AAI to DDD modes (26.7 ± 14.2 to 21.6 ± 11.9 mW/m, P <.001), whereas the mean diastolic EL did not change (28.7 ± 16.4 to 23.9 ± 19.7 mW/m, P =.130). Conclusions: RV pacing increased the mean systolic EL in patients without HCM. Conversely, RV pacing decreased the mean systolic EL in patients with HCM. [ABSTRACT FROM AUTHOR]

Aim: Fear conditioning tests are intended to elucidate a subject's ability to associate a conditioned stimulus with an aversive, unconditioned stimulus, such as footshock. Among these tests, a paradigm related to precise cortical functions would be increasingly important in drug screening for disorders such as schizophrenia and dementia. Therefore, we established a new fear conditioning paradigm using a visual cue in mice. In addition, the validity of the test was evaluated using a genetically engineered mouse, heterozygous deficient in Mdga1 (Mdga1+/‐), which is related to schizophrenia. Results: Mice were given footshocks associated with a visual cue of moving gratings at training in 25‐minute sessions. The mice showed the conditioned response of freezing behavior to the visual stimulus at testing 24 hours after the footshocks. In the test for validation, the Mdga1+/‐ deficient mice showed significantly less freezing than wild‐type mice. Conclusion: The visually cued fear conditioning paradigm with moving gratings has been established, which is experimentally useful to evaluate animal cortical functions. The validity of the test was confirmed for Mdga1‐deficient mice with possible deficiency in cortical functions. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM), a lethal brain tumor developing in the white matter of the adult brain, contains a small population of GBM stem cells (GSCs), which potentially cause chemotherapeutic resistance and tumor recurrence. However, the mechanisms underlying the pathogenesis and maintenance of GSCs remain largely unknown. A recent study reported that incorporation of ribosomes and ribosomal proteins into somatic cells promoted lineage trans‐differentiation toward multipotency. This study aimed to investigate the mechanism underlying stemness acquisition in GBM cells by focusing on 40S ribosomal protein S6 (RPS6). RPS6 was significantly upregulated in high‐grade glioma and localized at perivascular, perinecrotic, and border niches in GBM tissues. siRNA‐mediated RPS6 knock‐down significantly suppressed the characteristics of GSCs, including their tumorsphere potential and GSC marker expression; STAT3 was downregulated in GBM cells. RPS6 overexpression enhanced the tumorsphere potential of GSCs and these effects were attenuated by STAT3 inhibitor (AG490). Moreover, RPS6 expression was significantly correlated with SOX2 expression in different glioma grades. Immunohistochemistry data herein indicated that RPS6 was predominant in GSC niches, concurrent with the data from IVY GAP databases. Furthermore, RPS6 and other ribosomal proteins were upregulated in GSC‐predominant areas in this database. The present results indicate that, in GSC niches, ribosomal proteins play crucial roles in the development and maintenance of GSCs and are clinically associated with chemoradioresistance and GBM recurrence. [ABSTRACT FROM AUTHOR]

New energy saving methods are required in the industrial sector to address global climate change and resource depletion. Carbon fiber reinforced plastic (CFRP) has attracted considerable attention as a structural material that can improve energy efficiency by weight reduction. The application of CFRP to machine tools has already been realized; however, the dynamic characteristics of the position control system for CFRP machine tools have not been investigated. In this study, the mechanical properties affecting the positioning performance were experimentally evaluated using a rotary stage that could be switched to different structural materials. This study can be useful as a guideline for position control systems and the mechanical design of a CFRP stage and contribute toward achieving higher energy efficiency. [ABSTRACT FROM AUTHOR]

The pseudo‐polyrotaxane structure of [(H‐bpy+)‐ (DB‐24‐crown‐8)]∞ (H‐bpy+ = monoprotonated 4,4‐bipyridinium; DB‐24‐crown‐8 = dibenzo‐24‐crown‐8) has been incorporated into the anion radical salt [Ni(dmit)2]− (dmit2− = 1,3‐dithiole‐2‐thione‐4,5‐dithiolate). (H‐bpy+)(DB‐24‐crown‐8)[Ni(dmit)2]− crystallized as two polymorphs, crystals 1 and 2. Crystal 1 was found to have a lower density and looser packing structure in which H‐bpy+ forms a one‐dimensional hydrogen‐bonding chain that passes though the crown ether ring of DB‐24‐crown‐8. DB‐24‐crown‐8 adopts a U‐shaped conformation in which two phenylene rings sandwich one of the pyridyl rings of H‐bpy+ to stabilize the structure. The [Ni(dmit)2]− anions are arranged in a layer parallel to the (10) plane with uniform side‐by‐side interactions. A structural phase transition was observed at 235 K, accompanied by ordering of the polyrotaxane structure. In crystal 1, at 173 K, H‐bpy+ is twisted around the central C−C bond, which perturbs the arrangement of [Ni(dmit)2]− through short C−H⋅⋅⋅S contacts. As a result, the semiconducting behavior, with an activation energy of 0.21 eV, becomes insulating below 235 K. The crystal exhibits ferromagnetic interactions because of the weak side‐by‐side interactions between [Ni(dmit)2]− anions. Crystal 2 has a similar pseudo‐polyrotaxane structure but showed no phase transition. This suggests that the looser crystal packing in crystal 1 induces the structural change of the pseudo‐polyrotaxane, perturbing the electron system of [Ni(dmit)2]−. [ABSTRACT FROM AUTHOR]

Summary: Heavy‐ion beams have been widely utilized as a novel and effective mutagen for mutation breeding in diverse plant species, but the induced mutation spectrum is not fully understood at the genome scale. We describe the development of a multiplexed and cost‐efficient whole‐exome sequencing procedure in rice, and its application to characterize an unselected population of heavy‐ion beam‐induced mutations. The bioinformatics pipeline identified single‐nucleotide mutations as well as small and large (>63 kb) insertions and deletions, and showed good agreement with the results obtained with conventional polymerase chain reaction (PCR) and sequencing analyses. We applied the procedure to analyze the mutation spectrum induced by heavy‐ion beams at the population level. In total, 165 individual M2 lines derived from six irradiation conditions as well as eight pools from non‐irradiated 'Nipponbare' controls were sequenced using the newly established target exome sequencing procedure. The characteristics and distribution of carbon‐ion beam‐induced mutations were analyzed in the absence of bias introduced by visual mutant selections. The average (±SE) number of mutations within the target exon regions was 9.06 ± 0.37 induced by 150 Gy irradiation of dry seeds. The mutation frequency changed in parallel to the irradiation dose when dry seeds were irradiated. The total number of mutations detected by sequencing unselected M2 lines was correlated with the conventional mutation frequency determined by the occurrence of morphological mutants. Therefore, mutation frequency may be a good indicator for sequencing‐based determination of the optimal irradiation condition for induction of mutations. Significance Statement: We developed a multiplexed and cost‐efficient whole‐exome sequencing procedure and bioinformatics filtering pipeline for rice, and demonstrated the rapid identification of authentic mutations from a large dataset of candidate mutations. We applied this technique for the characterization of mutation spectra by heavy‐ion beams in the absence of the mutant selection, and showed that 9.06 ± 0.37 (average ± SE) mutations were induced within the target exon regions by 150 Gy irradiation of dry seeds in rice. [ABSTRACT FROM AUTHOR]

We isolated acold sensitive virescent1(csv1) mutant from a rice (Oryza sativaL.) population mutagenized by carbon ion irradiation. The mutant exhibited chlorotic leaves during the early growth stages, and produced normal green leaves as it grew. The growth ofcsv1plants displayed sensitivity to low temperatures. In addition, the mutant plants that were transferred to low temperatures at the fifth leaf stage produced chlorotic leaves subsequently. Genetic and molecular analyses revealed translocation of a 13-kb genomic fragment that disrupted the causative gene (CSV1; LOC_Os05g34040).CSV1encodes a plastid-targeted oxidoreductase-like protein conserved among land plants, green algae, and cyanobacteria. Furthermore,CSV1transcripts were more abundant in immature than in mature leaves, and they did not markedly increase or decrease with temperature. Taken together, our results indicate thatCSV1supports chloroplast development under cold stress conditions, in both the early growth and tillering stages in rice. We isolated and characterized the rice virescent mutant csv1. The mutant showed low temperature sensitivity not only early growth stages but also the tillering stage. [ABSTRACT FROM AUTHOR]

A 57‐year‐old man was admitted to our hospital due to syncopal attack. He was diagnosed with Brugada syndrome due to which a subcutaneous implantable cardiac defibrillator (S‐ICD) was inserted using the standard technique. Two hours after the implantation, he experienced inappropriate shock while conscious. Device interrogation revealed a contentious baseline shift and frequent oversensing of low‐amplitude signals, which was followed by a shock. Lateral chest X‐ray revealed subcutaneous air surrounding the proximal electrode. Another inappropriate shock could be avoided by changing the sensing vector. The subcutaneous air was completely resolved 7 days after implantation. [ABSTRACT FROM AUTHOR]

Although glioblastoma (GBM) stem-like cells (GSCs), which retain chemo-radio resistance and recurrence, are key prognostic factors in GBM patients, the molecular mechanisms of GSC development are largely unknown. Recently, several studies revealed that extrinsic ribosome incorporation into somatic cells resulted in stem cell properties and served as a key trigger and factor for the cell reprogramming process. In this study, we aimed to investigate the mechanisms underlying GSCs development by focusing on extrinsic ribosome incorporation into GBM cells. Ribosome-induced cancer cell spheroid (RICCS) formation was significantly upregulated by ribosome incorporation. RICCS showed the stem-like cell characters (number of cell spheroid, stem cell markers, and ability for trans differentiation towards adipocytes and osteocytes). In RICCS, the phosphorylation and protein expression of ribosomal protein S6 (RPS6), an intrinsic ribosomal protein, and STAT3 phosphorylation were upregulated, and involved in the regulation of cell spheroid formation. Consistent with those results, glioma-derived extrinsic ribosome also promoted GBM-RICCS formation through intrinsic RPS6 phosphorylation. Moreover, in glioma patients, RPS6 phosphorylation was dominantly observed in high-grade glioma tissues, and predominantly upregulated in GSCs niches, such as the perinecrosis niche and perivascular niche. Those results indicate the potential biological and clinical significance of extrinsic ribosomal proteins in GSC development. [ABSTRACT FROM AUTHOR]

Heavy-ion beam, a type of ionizing radiation, has been applied to plant breeding as a powerful mutagen and is a promising tool to induce large deletions and chromosomal rearrangements. The effectiveness of heavy-ion irradiation can be explained by linear energy transfer (LET; keV µm -1 ). Heavy-ion beams with different LET values induce different types and sizes of mutations. It has been suggested that deletion size increases with increasing LET value, and complex chromosomal rearrangements are induced in higher LET radiations. In this study, we mapped heavy-ion beam-induced deletions detected in Arabidopsis mutants to its genome. We revealed that deletion sizes were similar between different LETs (100 to 290 keV μm -1 ), that their upper limit was affected by the distribution of essential genes, and that the detected chromosomal rearrangements avoid disrupting the essential genes. We also focused on tandemly arrayed genes (TAGs), where two or more homologous genes are adjacent to one another in the genome. Our results suggested that 100 keV µm -1 of LET is enough to disrupt TAGs and that the distribution of essential genes strongly affects the heritability of mutations overlapping them. Our results provide a genomic view of large deletion inductions in the Arabidopsis genome., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ishii, Kazama, Hirano, Fawcett, Sato, Hirai, Sakai, Shirakawa, Ohbu and Abe.)

We performed cavotricuspid isthmus (CTI) linear ablation for atrial flutter; however, the tachycardia cycle length was not changed at all. In such cases, repeated or broad line ablation is usually performed. We presented that high-density three-dimensional mapping after the first CTI linear ablation, which revealed the complex tachycardia circuit with the epicardial and endocardial breakthrough., Competing Interests: Authors declare no conflict of interests for this article., (© 2021 The Authors. Journal of Arrhythmia published by John Wiley & Sons Australia, Ltd on behalf of the Japanese Heart Rhythm Society.)

Background: The incidence of new-onset atrial high-rate episode (AHRE) is higher among patients with cardiac implantable electronic devices (CIEDs) than in the general population. We sought to elucidate the clinical factors associated with AHRE in CIED patients, including P-wave dispersion (PWD) in sinus rhythm. Methods and Results: In all, 101 patients with CIEDs newly implanted between 2010 and 2014 were included in the study. PWD was measured at the time of device implantation via a body-surface electrocardiogram. AHRE was defined as any episode of sustained atrial tachyarrhythmia (>170 beats/min) recorded in the device's memory. Patients were divided into an AHRE (n=34) and non-AHRE (n=67) group based on the presence or absence of AHRE within 1 year of device implantation and compared. Mean (±SD) patient age was 75±11 years. A greater incidence of sick sinus syndrome (P=0.05) and longer PWD (62.6±13.1 vs. 38.2±13.9 ms; P<0.0001) were apparent in the AHRE than non-AHRE group. Multivariate analysis revealed that PWD was an independent predictor of new-onset AHRE (odds ratio 1.11; 95% confidence interval 1.06-1.17; P<0.0001). In logistic regression analysis, receiver-operating characteristic curve analysis (area under the curve 0.90; P<0.001) suggested the best cut-off value for PWD was 48 mm (sensitivity 73.8%, specificity 77.9%). Conclusions: PWD is a simple but feasible predictor of new-onset AHRE in patients with CIEDs., Competing Interests: J.A. is a member of Circulation Reports’ Editorial Team. The authors declare there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported herein., (Copyright © 2021, THE JAPANESE CIRCULATION SOCIETY.)