著者
Sakyo Hirai Hirotaka Sato Toshihiro Yamamura Koichi Kato Mariko Ishikawa Hirotaka Sagawa Jiro Aoyama Shoko Fujii Kyohei Fujita Toshinari Arai Kazutaka Sumita
出版者
The Japanese Society for Neuroendovascular Therapy
雑誌
Journal of Neuroendovascular Therapy (ISSN:18824072)
巻号頁・発行日
pp.oa.2022-0026, (Released:2022-07-30)
参考文献数
29

Objective: CT perfusion (CTP) provides various hemodynamic parameters. However, it is unclear which CTP parameters are useful in predicting clinical outcome in patients with acute ischemic stroke (AIS).Methods: Between February 2019 and June 2021, patients with anterior circulation large-vessel occlusion who achieved successful recanalization within 8 hours after stroke onset were included. The relative CTP parameter values analyzed by the reformulated singular value decomposition (SVD) method in the affected middle cerebral artery territories compared to those in the unaffected side were calculated. In addition, the ischemic core volume (ICV) was evaluated using a Bayesian Vitrea. The final infarct volume (FIV) was assessed by 24-hour MRI. The correlation between these CTP-derived values and clinical outcome was assessed.Results: Forty-two patients were analyzed. Among the CTP-related parameters, the ICV, relative cerebral blood volume (rCBV), and relative mean transit time (rMTT) showed a strong correlation with the FIV (ρ = 0.74, p <0.0001; ρ = −0.67, p <0.0001; and ρ = −0.66, p <0.0001, respectively). In multivariate analysis, rCBV, rMTT, and ICV were significantly associated with good functional outcome, which was defined as a modified Rankin Scale score ≤2 (OR, 6.87 [95% CI, 1.20–39.30], p = 0.0303; OR, 11.27 [95% CI, 0.97–130.94], p = 0.0269; and OR, 36.22 [95% CI, 2.78–471.18], p = 0.0061, respectively).Conclusions: Among the CTP parameters analyzed by the SVD deconvolution algorithms, rCBV and rMTT could be useful imaging predictors of response to recanalization in patients with AIS, and the performances of these variables were similar to that of the ICV calculated by the Bayesian Vitrea.
著者
Meng GUO Hiromasa MORIYAMA Yoshihiro HARADA Hideaki NISHIMURA Manabu KODAMA Shuichiro HIRAI Masami KADONAGA Koichi KATO Kazuyoshi FUSHINOBU
出版者
The Imaging Society of Japan
雑誌
日本画像学会誌 (ISSN:13444425)
巻号頁・発行日
vol.60, no.6, pp.580-591, 2021-12-10 (Released:2021-12-11)
参考文献数
20
被引用文献数
1

Theoretical models to integrate pores size distribution and to analyze permeation of a droplet into coated paper are proposed. Droplet permeation into porous media plays an important role in the image formation of inkjet printing. In this study, pores size distribution of porous media of different coated papers was investigated using nitrogen adsorption-desorption method. Based on the pores size distribution, theoretical model for estimating permeation amount into coated paper of pico-scale droplet was proposed, with the consideration of Lucas-Washburn equation. In order to verify the theoretical model, experiments of droplet observation with pure water and several propylene glycol (PG) aqueous solutions were conducted. For some paper samples, results of theoretical calculation and experiments generally agree well. However, there are cases where the theoretical predictions show discrepancy. Possible reasons are considered to be deviation of pores size distribution. Moreover, the accuracy of estimated evaporation volume by Hu and Larson's Equation, and the complex shape of the pores in coated layer also contribute to the errors. The effect of these factors still needs to be further explored.
著者
Tomoki Nakayoshi Koichi Kato Eiji Kurimoto Akifumi Oda
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.44, no.7, pp.967-975, 2021-07-01 (Released:2021-07-01)
参考文献数
39
被引用文献数
1

Isomerized aspartic acid (Asp) residues have previously been identified in various aging tissues, and are suspected to contribute to age-related diseases. Asp-residue isomerization occurs nonenzymatically under physiological conditions, resulting in the formation of three types of isomerized Asp (i.e., L-isoAsp, D-Asp, and D-isoAsp) residues. Asp-residue isomerization often accelerates protein aggregation and insolubilization, making structural biology analyses difficult. Recently, Sakaue et al. reported the synthesis of a ribonuclease A (RNase A) in which Asp121 was artificially replaced with different isomerized Asp residues, and experimentally demonstrated that the enzymatic activities of these artificial mutants were completely lost. However, their structural features have not yet been elucidated. In the present study, the three-dimensional (3D) structures of these artificial-mutant RNases A were predicted using molecular dynamics (MD) simulations. The 3D structures of wild-type and artificial-mutant RNases A were converged by 3000-ns MD simulations. Our computational data show that the structures of the active site and the formation frequencies of the appropriate catalytic dyad structures in the artificial-mutant RNases A were quite different from wild-type RNase A. These computational findings may provide an explanation for the experimental data which show that artificial-mutant RNases A lack enzymatic activity. Herein, MD simulations have been used to evaluate the influences of isomerized Asp residues on the 3D structures of proteins.