マウスガードの自律神経活動への影響 : 瞳孔フラッシュ応答による定量的評価

Background:Recently, it has been reported that mouth guards (MGs), which reduce the incidence and severity of traumatic oral injuries in contact sports, may actually affect sports performance. We have observed that a majority of subjects showed improved dynamic visual acuity during head rotation when using a MG, but subjects who were unwilling to use a MG showed the opposite effect. Thus, we hypothesized that unpleasant sensations due to MGs may decrease sports performance.Methods:In this study, we measured autonomic nervous system activity to evaluate unpleasant sensations objectively and quantitatively by measuring the pupillary flash response (PFR) and heart rate variability (HRV), before, during, and after wearing 3- and 5-mm-thick custom-made MGs in 10 healthy subjects.Results:It was found that the 5-mm MG had a higher incidence of unpleasant sensations (50% of subjects) than did the 3-mm MG (10%). PFR (not HRV) analysis showed that both sympathetic and parasympathetic nervous system activities increased in subjects with unpleasant sensations.Conclusions:We suggest that the unpleasant sensation induced this unusual autonomic nervous system response, which could not be detected by traditional methods such as HRV analysis. By using PFR analysis, it is possible to make MGs without unpleasant sensations for better sports performance.博士（医学）・乙第1306号・平成24年11月27日Copyright © 2012 Japanese Stomatological Society. Published by Elsevier Japan K

VLBI Astrometry of the Semiregular Variable RX Bootis

We present distance measurement of the semiregular variable RX Bootis (RX Boo) with its annual parallax. Using the unique dual-beam system of the VLBI Exploration of Radio Astrometry (VERA) telescope, we conducted astrometric observations of a water maser spot accompanying RX Boo referred to the quasar J1419+2706 separated by 1.69 degrees from RX Boo. We have measured the annual parallax of RX Boo to be 7.31 +/- 0.50 mas, corresponding to a distance of 136 +10/-9 pc, from the one-year monitoring observation data of one maser spot at VLSR = 3.2 km/s. The distance itself is consistent with the one obtained with Hipparcos. The distance uncertainty is reduced by a factor of two, allowing us to determine the stellar properties more accurately. Using our distance, we discuss the location of RX Boo in various sequences of Period-Luminosity (PL) relations. We found RX Boo is located in the Mira sequence of PL relation. In addition, we calculated the radius of photosphere and the mass limitation of RX Boo and discussed its evolutionary status.Comment: 8 pages, 4figure

Evolution of the primate glutamate taste sensor from a nucleotide sensor

霊長類におけるグルタミン酸の旨味の起源 --体の大きな霊長類は旨味感覚で葉の苦さを克服--. 京都大学プレスリリース. 2021-08-30.Taste perception plays an essential role in food selection. Umami (savory) tastes are sensed by a taste receptor complex, T1R1/T1R3, that detects proteinogenic amino acids. High sensitivity to l-glutamate (l-Glu) is a characteristic of human T1R1/T1R3, but the T1R1/T1R3 of other vertebrates does not consistently show this l-Glu response. Here, we demonstrate that the l-Glu sensitivity of T1R1/T1R3 is a derived state that has evolved repeatedly in large primates that rely on leaves as protein sources, after their divergence from insectivorous ancestors. Receptor expression experiments show that common amino acid substitutions at ligand binding sites that render T1R1/T1R3 sensitive to l-Glu occur independently at least three times in primate evolution. Meanwhile T1R1/T1R3 senses 5′-ribonucleotides as opposed to l-Glu in several mammalian species, including insectivorous primates. Our chemical analysis reveal that l-Glu is one of the major free amino acids in primate diets and that insects, but not leaves, contain large amounts of free 5′-ribonucleotides. Altering the ligand-binding preference of T1R1/T1R3 from 5′-ribonucleotides to l-Glu might promote leaf consumption, overcoming bitter and aversive tastes. Altogether, our results provide insight into the foraging ecology of a diverse mammalian radiation and help reveal how evolution of sensory genes facilitates invasion of new ecological niches

Protein C activity as a potential prognostic factor for nursing home-acquired pneumonia

[Introduction] Despite the poor prognosis for nursing home acquired pneumonia (NHAP), a useful prognostic factor is lacking. We evaluated protein C (PC) activity as a predictor of in-hospital death in patients with NHAP and community-acquired pneumonia (CAP). [Methods] This prospective, observational study included all patients hospitalized with pneumonia between July 2007 and December 2012 in a single hospital. We measured PC activity at admission and investigated whether it was different between survivors and non-survivors. We also examined whether PC activity 20 mg/dL, respiratory rate >30/min, and blood pressure 65). When it was a useful prognostic factor for pneumonia, we combined PC activity with the existing prognostic scores, the pneumonia severity index (PSI) and CURB-65, and analyzed its additional effect by comparing the areas under the receiver operating characteristic curves (AUCs) of the modified and original scores. [Results] Participants comprised 75 NHAP and 315 CAP patients. PC activity was lower among non-survivors than among survivors in NHAP and all-pneumonia (CAP+NHAP). PC activity <55% was a useful prognostic predictor for NHAP (Odds ratio 7.39 (95% CI; 1.59–34.38), and when PSI or CURB-65 was combined with PC activity, the AUC improved (from 0.712 to 0.820 for PSI, and 0.657 to 0.734 for CURB-65). [Conclusions] PC activity was useful for predicting in-hospital death of pneumonia, especially in NHAP, and became more useful when combined with the PSI or CURB-65

食生活の多様性とうつ病および自殺の有病率との関連 ―26年間の国際比較研究―

Purpose: This study aimed to determine the associations of dietary diversity with depression and suicide rates by an ecological analysis using 26-years worldwide statistics.Methods: Average food supply and energy supply by country, excluding loss between production and household, were obtained from the Food and Agriculture Organization of the United Nations Statistics Division database (FAOSTAT). Dietary diversity scores were calculated from food group classifications. Age-standardized depression prevalence and suicide rates per 100,000 people by country were obtained from the Global Burden of Disease (GBD) 2017 database. The association between food diversity scores and depression prevalence and suicide rates was analyzed by a mixed effects model controlling for covariates in 137 countries with populations of 1 million or greater.Results: A significant negative association was found in the analysis of the relationship between dietary diversity and the prevalence of major depression in the model controlled for all covariates [β (se) = –225.6 (61.9), p < 0.001]. In addition, a significant negative association between dietary diversity and the suicide rate was also found in the model controlled for all covariates [β (se) = –3.08 (1.50), p < 0.05].Conclusion: Dietary diversity was significantly negatively associated with the rates of major depression and suicide. Diets rich in foods may reduce the prevalence of depression and suicide rate.【目的】本研究は、26年間の世界的な統計を用いた生態学的分析により、食生活の多様性とうつ病や自殺率との関連を明らかにすることを目的とした。【方法】生産と家庭間の喪失を除く国別平均食料供給量とエネルギー供給量を国連食糧農業機関統計局データベース（FAOSTAT）から入手した。食物群分類から食事多様性スコアを算出した。年齢標準化された国別の人口10万人当たりのうつ病有病率と自殺率は、Global Burden of Disease（GBD）2017データベースから取得した。人口100万人以上の137カ国を対象に、食品多様性スコアとうつ病有病率および自殺率との関連を、共変量を制御した混合効果モデルで解析した。【結果】食生活の多様性とうつ病の有病率との関係を分析したところ、すべての共変量を調整したモデルにおいて、有意な負の関連が認められた［β（se）＝－225.6（61.9）、p < 0.001］。さらに、食生活の多様性と自殺率との間の有意な負の関連も、すべての共変量を調整したモデルで認められた［β（se）= －3.08（1.50）、p < 0.05］。【結論】食生活の多様性は、うつ病および自殺の発生率と有意に負の関連があった。食物を豊富に含む食事は、うつ病や自殺を減少させる可能性がある

Variation in ligand responses of the bitter taste receptors TAS2R1 and TAS2R4 among New World monkeys

Background New World monkeys (NWMs) are unique in that they exhibit remarkable interspecific variation in color vision and feeding behavior, making them an excellent model for studying sensory ecology. However, it is largely unknown whether non-visual senses co-vary with feeding ecology, especially gustation, which is expected to be indispensable in food selection. Bitter taste, which is mediated by bitter taste receptors (TAS2Rs) in the tongue, helps organisms avoid ingesting potentially toxic substances in food. In this study, we compared the ligand sensitivities of the TAS2Rs of five species of NWMs by heterologous expression in HEK293T cells and calcium imaging. Results We found that TAS2R1 and TAS2R4 orthologs differ in sensitivity among the NWM species for colchicine and camphor, respectively. We then reconstructed the ancestral receptors of NWM TAS2R1 and TAS2R4, measured the evolutionary shift in ligand sensitivity, and identified the amino acid replacement at residue 62 as responsible for the high sensitivity of marmoset TAS2R4 to colchicine. Conclusions Our results provide a basis for understanding the differences in feeding ecology among NWMs with respect to bitter taste

Human AK2 links intracellular bioenergetic redistribution to the fate of hematopoietic progenitors

AK2 is an adenylate phosphotransferase that localizes at the intermembrane spaces of the mitochondria, and its mutations cause a severe combined immunodeficiency with neutrophil maturation arrest named reticular dysgenesis (RD). Although the dysfunction of hematopoietic stem cells (HSCs) has been implicated, earlier developmental events that affect the fate of HSCs and/or hematopoietic progenitors have not been reported. Here, we used RD-patient-derived induced pluripotent stem cells (iPSCs) as a model of AK2-deficient human cells. Hematopoietic differentiation from RD-iPSCs was profoundly impaired. RD-iPSC-derived hemoangiogenic progenitor cells (HAPCs) showed decreased ATP distribution in the nucleus and altered global transcriptional profiles. Thus, AK2 has a stage-specific role in maintaining the ATP supply to the nucleus during hematopoietic differentiation, which affects the transcriptional profiles necessary for controlling the fate of multipotential HAPCs. Our data suggest that maintaining the appropriate energy level of each organelle by the intracellular redistribution of ATP is important for controlling the fate of progenitor cells