Isothermal remanent magnetization and the spin dimensionality of spin glasses

The isothermal remanent magnetization is used to investigate dynamical magnetic properties of spatially three dimensional spin glasses with different spin dimensionality (Ising, XY, Heisenberg). The isothermal remanent magnetization is recorded vs. temperature after intermittent application of a weak magnetic field at a constant temperature $T_h$. We observe that in the case of the Heisenberg spin glasses, the equilibrated spin structure and the direction of the excess moment are recovered at $T_h$. The isothermal remanent magnetization thus reflects the directional character of the Dzyaloshinsky-Moriya interaction present in Heisenberg systems.Comment: tPHL2e style; 7 page, 3 figure

マウスリンパ組織のレプチンレセプター発現細胞の検出

Leptin, the product of the ob gene expressed in adipocytes, is shown to influence energy intake and expenditure, proliferation of CD^ T cells, neovascularization and intracellular triglycerides homeostasis in non-adipocytes. Leptin acts on target cells through receptor (OB-R). There are at least five different types of OB-R in mouse due to alternative splicing from db gene transcripts.OB-Ra〜OB-Rd share identical extracellular and transmembrane domains and JAK binding consensus sequence at cytoplasmic domain. Only OB-Rb has an additional STAT binding motif and is essential for most of leptin' s physiological functions through JAK-STAT pathway. OB-Ra is also reported to transduct weakly leptin's signal through JAK-phospholyration pathway. On this paper we examined which kinds of cell express OB-Ra or OB-Rb in lymphoid and fat tissues of the mouse. Both types of OB-R were detected in thymus, spleen and gastrolienal fat tissue by RTPCR method, then the constitutive cells were separated from dissected tissues and cultured in GIT medium with 10% heat-inactivated FBS. Primary cultured lymphocytes isolated from thymus or spleen expressed both OB-Ra and OB-Rb. On the other hand, in adhesive cells dispersed with enzymatic digestion and primary cultured OB-Rb was not detected, though OB-Ra detectable.Similarly, primary cultured adhesive cells of gastrolienal fat tissue expressed only OB-Ra. It is therefore most parsimonious to conclude that only lymphocytes express OB-Rb and response effectively to leptin in thymus

『日本語日常会話コーパス』の転記基準と作業工程

会議名: 言語資源活用ワークショップ2016, 開催地: 国立国語研究所, 会期: 2017年3月7日-8日, 主催: 国立国語研究所 コーパス開発センター国立国語研究所では，今年の四月から「大規模日常会話コーパスに基づく話し言葉の多角的研究」プロジェクトを進めている。このプロジェクトでは，さまざまなタイプの日常会話200時間をバランス良く収録した大規模なコーパス『日本語日常会話コーパス』を構築し，それに基づく分析を通じて，日常会話を含む話し言葉の特性を多角的に解明することを目指している。本コーパスには，日常場面で行われる現実の会話が収録される。こうした会話には，極めてくだけた表現も頻出する。こうしたデータを多人数で書き起こしをするためには，文字化をするための基準を明確に定める必要がある。また，大量の会話を限られた期間で書き起こすために，効率的に作業をするための工夫が必要になる。本発表では，書き起こしの基準と効率的に作業を行うために用いている方法について紹介する

Effect of Maillard Reacted Peptides on Human Salt Taste and the Amiloride-Insensitive Salt Taste Receptor (TRPV1t)

Maillard reacted peptides (MRPs) were synthesized by conjugating a peptide fraction (1000–5000 Da) purified from soy protein hydrolyzate with galacturonic acid, glucosamine, xylose, fructose, or glucose. The effect of MRPs was investigated on human salt taste and on the chorda tympani (CT) taste nerve responses to NaCl in Sprague–Dawley rats, wild-type, and transient receptor potential vanilloid 1 (TRPV1) knockout mice. MRPs produced a biphasic effect on human salt taste perception and on the CT responses in rats and wild-type mice in the presence of NaCl + benzamil (Bz, a blocker of epithelial Na+ channels), enhancing the NaCl response at low concentrations and suppressing it at high concentrations. The effectiveness of MRPs as salt taste enhancers varied with the conjugated sugar moiety: galacturonic acid = glucosamine > xylose > fructose > glucose. The concentrations at which MRPs enhanced human salt taste were significantly lower than the concentrations of MRPs that produced increase in the NaCl CT response. Elevated temperature, resiniferatoxin, capsaicin, and ethanol produced additive effects on the NaCl CT responses in the presence of MRPs. Elevated temperature and ethanol also enhanced human salt taste perception. N-(3-methoxyphenyl)-4-chlorocinnamid (a blocker of TRPV1t) inhibited the Bz-insensitive NaCl CT responses in the absence and presence of MRPs. TRPV1 knockout mice demonstrated no Bz-insensitive NaCl CT response in the absence or presence of MRPs. The results suggest that MRPs modulate human salt taste and the NaCl + Bz CT responses by interacting with TRPV1t

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

Highly efficient renaturation of β-lactamase isolated from moderately halophilic bacteria

AbstractMost, if not all, β-lactamases reported to date are irreversibly denatured at 60–70°C. Here, we found that a halophilic β-lactamase from the moderately halophilic bacterium Chromohalobacter sp. 560 was highly stable against heat inactivation: it retained ∼75% of its activity after boiling for 5 min in the presence of 0.2 M NaCl, suggesting that the protein either incompletely denatures during the boiling process or readily renatures upon cooling to the assay temperature. Circular dichroism showed a complete unfolding at 60°C and a full reversibility, indicating that the observed activity after boiling is due to efficient refolding following heat denaturation. The enzyme showed optimal activity at 50–60°C, indicating that an increase in activity with temperature offsets the thermal denaturation. The gene bla was cloned, and the primary structure of the enzyme was deduced to be highly abundant in acidic amino acid residues, one of the characteristics of halophilic proteins. Despite its halophilic nature, the enzyme refolds in low salt media after heat denaturation