216 research outputs found

    Autonomic Nervous System Activity During a Speech Task

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    Previous research has reported that different coping types (active or passive) are required depending on the stress-inducing task. The aim of this study was to examine the autonomic nervous response during speech tasks that require active coping, by using Lorenz plot analysis. Thirty-one university students participated in this study (M = 21.03 years, SD = 2.27). This study included 3 phases: (1) resting phase, (2) silent reading phase, and (3) reading aloud phase. Autonomic nervous system responses were recorded in each phase. We asked participants to evaluate their subjective states (arousal, valence, and mood) after the silent reading phase and the reading aloud phase. We observed that the cardiac sympathetic index (CSI) for the sympathetic nervous response was significantly higher during the reading aloud phase than during the silent reading phase. In contrast, the cardiac vagal index (CVI) for the parasympathetic nervous response was significantly higher during the reading aloud phase than during the resting phase. There were no significant differences between the resting phase and the silent reading phase in both cardiac sympathetic and CVIs. We also observed that the degree of arousal was significantly higher after the reading aloud phase than after the silent reading phase. Our findings indicate that the psychological load during silent reading is ineffective for activating the sympathetic nervous system. The sympathetic nervous response was activated in the reading aloud phase. Also, the parasympathetic nervous response in the reading aloud phase was activated compared with the resting phase. Reading aloud is necessary to adequately activate the parasympathetic nervous system by requiring participants to respire (i.e., expiration) more than during resting and silent reading tasks. The increase in the CVI likely stems from activating the parasympathetic nervous system during expiration. Although the speech task required participants to perform active coping, it was designed to activate both the sympathetic and parasympathetic nervous systems during expiration

    Bovine Insulin Filaments Induced by Reducing Disulfide Bonds Show a Different Morphology, Secondary Structure, and Cell Toxicity from Intact Insulin Amyloid Fibrils

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    AbstractAmyloid fibrils are associated with more than 20 diseases, including Alzheimer's disease and type II diabetes. Insulin is a 51-residue polypeptide hormone, with its two polypeptide chains linked by one intrachain and two interchain disulfide bonds, and has long been known to self-assemble in vitro into amyloid fibrils. We demonstrate here that bovine insulin forms flexible filaments in the presence of a reducing agent, Tris (2-carboxyethyl) phosphine. The insulin filaments, possibly formed due to partial reduction of S-S bonds in insulin molecules, differ from intact insulin fibrils in terms of their secondary structure. The insulin filaments were determined to have an antiparallel β-sheet structure, whereas the insulin fibrils have a parallel β-sheet structure. Of importance, the cell toxicity of the insulin filaments was remarkably lower than that of the insulin fibrils. This finding supports the idea that cell toxicity of amyloids correlates with their morphology. The remarkably low toxicity of the filamentous structure should shed new light on possible pharmacological approaches to the various diseases caused by amyloid fibrils

    Translation initiation at non-AUG codons mediated by weakened association of eukaryotic initiation factor (eIF) 2 subunits

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    The heterotrimeric eukaryotic initiation factor (eIF) 2 binds the initiator methionyl-tRNA in a GTP-dependent mode and delivers it to the 40 S ribosomal subunit. in the present study, we have identified amino acid residues in eIF2beta required for binding to eIF2gamma in yeast. Alteration of six residues in the central region of eIF2beta abolished this interaction, as determined by GST-pull down and two-hybrid assays, and leads to cell lethality. Substitution of (131)Tyr and (132)Ser by alanine residues ((YS)-Y-131), although abolishing the binding to eIF2gamma in these assays, resulted in a functional but defective protein in vivo, imparting a temperature-sensitive growth phenotype to cells. A dramatically weakened association of this mutant protein with eIF2gamma in vivo was shown by co-immunoprecipitation. the (YS)-Y-131 mutation in eIF2beta allows translation to initiate at non-AUG codons, as defined by the ability of cells carrying an initiator codon mutation in the HIS4 mRNA to grow in the absence of histidine. the combination of this mutation with the (254)Ser --> Tyr alteration, a previously isolated suppressor of initiator codon mutations which has been shown to increase the spontaneous GTP hydrolysis in the ternary complex, caused a recessive lethality, suggesting additive defects. Thus the impaired interaction of these two subunits represents a novel type of defect in eIF2 function, providing in vivo evidence that the strength of interaction between eIF2beta and eIF2gamma defines the correct usage of the AUG codon for translation initiation.Universidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, BrazilWeb of Scienc

    ライティング コミュニケーション オ トオシタ キョウシ ガクセイ セイト カン ノ シンライ カンケイ オ コウチク スル ホウホウ : クラス ジャーナル オ モチイタ ダイガク チュウガッコウ デノ ジレイ ショウカイ

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    教師にとって学生全員とコミュニケーションをとることは信頼関係を築くためや、クラスを運営していく上で必要なことですが、実際の教育現場では人数または時間の関係から十分なコミュニケーションをとる事は難しいと思います。本文が紹介するクラス・ジャーナルは教師ー学生・生徒間でコメントのやり取り等をするための用紙であり、私たちは、教師と学生・生徒がダイアローグを通してコミュニケーションをとることで、学生一人一人との関係性(relatedness)を高めることができると考えています。 また、クラス・ジャーナルを利用することによって、学生自身が学習状況を振り返ることができるほか、管理することが可能になります。ここでは、大学と中学校でのクラス・ジャーナル活用術とそれぞれで現れた効果を記載しています
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