Inhibition of Blood Glucose Level Elevation by Low-Carbohydrate Ohagi in Healthy Adults

糖質は血糖値をもっとも上昇させるため，糖質を多く含む菓子類は糖尿病患者において制限されることが多い．和菓子は小豆に砂糖を加えた餡ともち米から成り，菓子類の中でも高糖質食品である．そこで餡ともち米からなるおはぎで糖質の低減が実現できれば他の和菓子への汎用性が高いと考え，エリスリトールを主とした甘味料と大麦を配合した低糖質おはぎを作成し，食後の血糖上昇とセカンドミール効果について検討した．対象は健常成人12名とし，方法は低糖質おはぎ，通常おはぎのいずれかの試験食を単盲検，クロスオーバーにより摂取し，試験食の摂取開始150分後に食事を摂取し，血糖値を測定した．その結果，低糖質おはぎは通常おはぎの摂取と比較し，食後15～30分の急峻な血糖上昇を有意に抑制し，セカンドミール後の血糖上昇曲線下面積（IAUC）では有意に低値を示した．健常成人における低糖質おはぎの摂取は，食後の血糖上昇を抑制する可能性が示唆された．[Aim] The aim of this study was to investigate the postprandial blood glucose response and second meal effect of low carbohydrate Ohagi prepared with barley and erythritol. [Method] The subjects were 12 healthy adults. The method was a single-blind, crossover design in which subjects consumed either low carbohydrate or regular Ohagi as the test meal. After 150 minutes, subjects consumed the meal and their blood glucose levels were measured. [Results] Low carbohydrate Ohagi showed a significantly lower rise in blood glucose levels 15 to 30 minutes after ingestion and a significantly lower glucose incremental areas under the curve (IAUC) after the second meal. [Conclusion] Consumption of low-carbohydrate Ohagi in healthy adults was suggested to improve postprandial glycemic response.departmental bulletin pape

IX Global Asia Education Program

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Recovering a Representative Conformational Ensemble from Underdetermined Macromolecular Structural Data

Structural analysis of proteins and nucleic acids is complicated by their inherent flexibility, conferred, for example, by linkers between their contiguous domains. Therefore, the macromolecule needs to be represented by an ensemble of conformations instead of a single conformation. Determining this ensemble is challenging because the experimental data are a convoluted average of contributions from multiple conformations. As the number of the ensemble degrees of freedom generally greatly exceeds the number of independent observables, directly deconvolving experimental data into a representative ensemble is an ill-posed problem. Recent developments in sparse approximations and compressive sensing have demonstrated that useful information can be recovered from underdetermined (ill-posed) systems of linear equations by using sparsity regularization. Inspired by these advances, we designed the Sparse Ensemble Selection (SES) method for recovering multiple conformations from a limited number of observations. SES is more general and accurate than previously published minimum-ensemble methods, and we use it to obtain representative conformational ensembles of Lys48-linked diubiquitin, characterized by the residual dipolar coupling data measured at several pH conditions. These representative ensembles are validated against NMR chemical shift perturbation data and compared to maximum-entropy results. The SES method reproduced and quantified the previously observed pH dependence of the major conformation of Lys48-linked diubiquitin, and revealed lesser-populated conformations that are preorganized for binding known diubiquitin receptors, thus providing insights into possible mechanisms of receptor recognition by polyubiquitin. SES is applicable to any experimental observables that can be expressed as a weighted linear combination of data for individual states

IV Guidance on Study Abroad

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Integrative structure modeling of the human RNA Polymerase II [<b>10</b>].

<p>The first round of modeling was performed using only the 2nm EM density map of the assembly from EMDB <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001244#pbio.1001244-Kostek1" target="_blank">[51]</a> and subunit comparative models from ModBase <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001244#pbio.1001244-Pieper1" target="_blank">[47]</a>, on the basis of the crystallographic structures of the yeast RNAPII proteins. The data were found to be insufficient to uniquely resolve the structure. To overcome this challenge, protein interaction networks extracted from BioGrid <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001244#pbio.1001244-Stark1" target="_blank">[48]</a> were added. The addition of these data resulted in a single structure. The scripts are available as part of IMP.</p

Reconstruction of 3D structures of MET antibodies from electron microscopy 2D class averages

<div><p>Dynamics of three MET antibody constructs (IgG1, IgG2, and IgG4) and the IgG4-MET antigen complex was investigated by creating their atomic models with an integrative experimental and computational approach. In particular, we used two-dimensional (2D) Electron Microscopy (EM) images, image class averaging, homology modeling, Rapidly exploring Random Tree (RRT) structure sampling, and fitting of models to images, to find the relative orientations of antibody domains that are consistent with the EM images. We revealed that the conformational preferences of the constructs depend on the extent of the hinge flexibility. We also quantified how the MET antigen impacts on the conformational dynamics of IgG4. These observations allow to create testable hypothesis to investigate MET biology. Our protocol may also help describe structural diversity of other antigen systems at approximately 5 Å precision, as quantified by Root-Mean-Square Deviation (RMSD) among good-scoring models.</p></div